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Amsterdam Criteria

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Aspirin for Hereditary Colorectal Cancer


The study shows that regularly taking the medicine cuts the risk of bowel cancer by more than 60% in those with a particular genetic predisposition to get the disease – as well as reducing the risk of other hereditary cancers.

Scientists who led the study said people with several family members with cancers other than breast, blood and prostate might be advised to start taking aspirin daily from the age of 45.

They said those without a family history of the disease might also consider doing so, but that they should make a personal assessment of the risks and benefits and get medical advice. Anyone thinking of taking the drug regularly should consult their doctor first.

Doctors already prescribe low, daily doses of aspirin to people at increased risk of heart attacks and strokes, and evidence has been growing of anti-cancer properties for 20 years. However, this is the first long-term, randomised controlled trial to show such an effect.

The trial involved people with Lynch syndrome, a genetic abnormality that predisposes carriers to develop bowel cancer and other solid organ cancers including endometrial, ovarian, stomach, kidney, oesophageal, brain and skin tumours.

The condition affects at least one in 1,000 people. Carriers are around 10 times as likely to develop cancer and often do so at a young age.

Professor John Burn of Newcastle University, who led the study, estimated that if all 30,000 or so people with Lynch syndrome in the UK were to start taking two aspirin tablets a day then some 10,000 cancers would be prevented over the next 30 years, saving about a thousand lives. The downside of the treatment is that around an extra thousand people would develop stomach ulcers as a side-effect.

“People with a genetic susceptibility are a model system,” said Burn, whose work is published online in the Lancet on Friday. “They are more sensitive to the environmental triggers to cancer.

“If we can do something to change cancer progression in people at high genetic risk, then that’s telling us what we might all benefit. But we are not making a recommendation for the general population. Everyone can take this evidence and make their own choice.

“In between you have the people who have a family history [of cancer]. Those individuals may well decide to put themselves on aspirin and that would be a reasonable conclusion from the data currently available.”

Between 1999 and 2005, about half of a group of 861 Lynch syndrome carriers were given two aspirins (600mg) a day, while the rest took placebos.

By 2010 those who had taken aspirin for at least two years were 63% less likely to have developed bowel cancer.

Looking at all forms of the disease, almost 30% of those in the placebo group developed a Lynch syndrome-related cancer, compared with 15% for those given aspirin.

The most common side effects associated with taking aspirin are gastrointestinal ulcers and stomach bleeding. There is also an very small increased risk of haemorrhagic stroke, in which a blood vessel in the brain bursts.

There was no difference in the proportions of the study groups suffering such side-effects.

Burn added that he takes low-dose aspirin tablets as a preventative measure. “That was a balanced judgment based on weighing risks and benefits. I know I might get an ulcer or a cerebral bleed but I’d rather not have a heart attack, stroke or cancer. That’s my choice.”

Aspirin is a synthetic version of the active component of willow bark, salicylic acid, which has been used as a medicine for its anti-inflammatory properties for hundreds of years. Salicylates also trigger programmed cell death to help diseased plants contain the spread of infection.

“It’s not a huge stretch to think that if salicylate induces programmed cell death in plants to kill infected cells, maybe it’s doing similar things in the animal kingdom to enhance the death of aberrant cells causing cancer,” said Prof Burn.

“This adds to the growing body of evidence showing the importance of aspirin, and aspirin-like drugs, in the fight against cancer and emphasises how critical it is to carry out long-term international research,” said Prof Chris Paraskeva, a bowel cancer expert at the University of Bristol.

The CAPP team have launched a website to recruit 3,000 people with Lynch syndrome worldwide to take part in a five-year trial to determine the best dose of aspirin to take.

 

A trial of methotrexate for cancer that has spread in people with a faulty MSH2 gene (MESH)


A trial of methotrexate for cancer that has spread in people with a faulty MSH2 gene (MESH)

This trial is looking at the chemotherapy drug methotrexate for people with a MSH2 gene fault who have cancer that started in the bowel, stomach, womb (endometrium), bladder, or lining of the urinary system (urothelium) and has spread.

Every cell contains DNA. This is the genetic information which controls how cells behave. In cancer cells, the DNA is changed or damaged. Cancers can have different types of changes in the DNA. One of these is when a gene called MSH2 is not working properly.

Doctors often use chemotherapy to treat cancer. But sometimes the cancer comes back after treatment and spreads elsewhere in the body.

Methotrexate is a chemotherapy drug that is used to treat some types of cancer. We know from research that methotrexate kills cancer cells when the MSH2 gene is not working properly. Researchers want to find out if it will help people with a faulty MSH2 gene who have cancer that has spread.

The aims of this trial are to

  • See how much methotrexate helps people in this situation
  • Learn more about the side effects

Recruitment

Start 08/04/2009

End 08/04/2014

Phase

Phase 2

Who can enter

You can enter this trial if you

  • Have cancer that started in your bowel, stomach, womb, bladder or urothelium and has grown into surrounding tissue, or has spread elsewhere in the body
  • Have cancer that did not respond to, or has come back after, treatment with standard chemotherapy, or you cannot have standard treatment for some reason
  • Have a MSH2 gene fault (the doctors will do tests to confirm this)
  • Have satisfactory blood test results
  • Are well enough to take part in the trial (performance status 0, 1 or 2)
  • Are at least 18 years old
  • Are willing to use reliable contraception during the trial and for 6 months afterwards if there is any chance you or your partner could become pregnant

You cannot enter this trial if you

  • Have already had treatment with methotrexate unless it was for a non cancerous condition and you finished treatment at least 5 years before you were diagnosed with cancer
  • Have had any other cancer in the last 10 years apart from non melanoma skin cancer or carcinoma of the cervix and the trial doctor thinks this could affect you taking part in this trial (If you have Lynch syndrome, you may be able to take part if you have had other cancers – the doctors will advise you on this)
  • Have had radiotherapy to a single area of cancer (a lesion) that the researchers will be measuring in this trial, unless the lesion has got bigger since you had radiotherapy
  • Have another medical condition that cannot be controlled with medication
  • Are pregnant or breastfeeding

Trial design

This phase 2 trial will recruit 56 people. Everybody taking part will have methotrexate.

You have methotrexate as an injection into a vein. The treatment only takes a few minutes. You have another injection a week later and then 2 weeks without any treatment. Each 3 week period is called a cycle of treatment. You have up to 6 cycles of treatment. But if the treatment is helping you, your doctor may talk to you about having it for longer.

During the trial, the researchers will take samples of blood, urine and a hair follicle (such as from an eyebrow). And they will get a sample of the tissue taken when you had surgery to remove your cancer or when you had a biopsy.

The researchers will use the samples to try to find substances they can measure in the body to help them tell how well the treatment is working. They call these substances biomarkers. And they will use the blood samples to look at your genes. This is to learn more about how genetic changes can lead to cancer and whether certain changes affect how people respond to treatment.

The trial team may also ask your permission to take an extra biopsy during treatment. This is to learn more about what effect the treatment has on the genetic make up of your cancer. If you don’t want to have this extra biopsy, you don’t have to. You can still take part in the trial.

All samples will be stored safely and may be used in the future, but only for research purposes.

You will be asked to fill out a questionnaire before you start treatment, just before the 2nd and 4th cycle of chemotherapy, and every 3 months for a year after you finish treatment. The questionnaire will ask about any side effects you have had and how you have been feeling. This is called a quality of life study.

The trial team will also ask you to fill out a short questionnaire which asks about other members of your family who have had cancer.

People taking part in this trial may also be asked to join extra studies looking at PET scans and MRI scans. Doctors want to find out if these scans can provide more information about bowel cancer with a faulty MSH2 gene.

You may be able to take part in one or both of these studies. Whether or not you are asked to take part will depend on where you are having your treatment and also where in your body the cancer is.

Hospital visits

You will see the doctors and have some tests before you start treatment. The tests include

  • Physical examination
  • Blood tests
  • CT scan
  • Chest X-ray
  • Heart trace (ECG)

You go to hospital twice in each 3 week cycle of treatment. You have regular blood tests. And after 9 weeks of treatment you have a CT scan to check that your cancer has not got any bigger. If the scan shows the cancer has grown, you will stop having the trial treatment and the doctors will discuss other treatment options with you. If the cancer has stayed the same size or got smaller, you will have the next 3 cycles of treatment and then another CT scan.

After you finish treatment you will see the trial doctors and have a CT scan every 3 months for up to 1 year.

If you do take part in the MRI or PET scan study (or both), you will have extra scans

  • Before you start treatment
  • After 2 weeks of treatment
  • When you finish treatment

Having an MRI scan takes about 15 to 30 minutes. If you have PET scans, you have an injection of a small amount of a radioactive drug first. Then you have to wait an hour before having the scan. The scan itself can take up to an hour.

Side effects

The side effects of methotrexate include

There is more information about the side effects of methotrexate on CancerHelp UK.

Location of trial

Top of Form

  • London
  • Sutton

For more information

Please note: we cannot help you to join a specific trial. Unless we state otherwise in this trial summary, you need to print this page and take it to your own doctor to discuss.

Find out how to join a trial or contact our cancer information nurses for other questions about cancer by phone (0808 800 4040), by email, or at

The Information Nurses

Cancer Research UK

Angel Building

407 St John Street

London
EC1V 4AD

Chief Investigator

Professor David Cunningham

Supported by: Institute of Cancer Research (ICR), The Royal Marsden NHS Foundation Trust

JAMA: Identification of Lynch Syndrome Among Patients With Colorectal Cancer


Identification of individuals at increased risk of hereditary cancer allows for the possibility of screening and early cancer detection, possibly resulting in decreased disease-specific mortality, and is the justification for germline genetic testing for specific cancer risk alleles. However, factors of prevalence and age-specific penetrance, effectiveness and invasiveness of screening procedures, and efficacy of early detection influence the potential benefit of such an approach.

For one of the most common hereditary cancer syndromes, Lynch syndrome (LS), also known as hereditary nonpolyposis colorectal cancer (HNPCC), various sets of clinical criteria, combined with pathologic phenotypic characteristics of tumor tissues in probands, have been used to identify individuals at risk in whom it is important to consider germline genetic testing for deleterious mutations in 1 of 4 DNA mismatch repair genes (MLH1, MSH2, MSH6, or PMS2). Lynch syndrome was originally defined by the “Amsterdam” clinical criteria as a history of at least 3 family members with histologically confirmed colorectal cancer (CRC) involving 2 generations with at least 1 person diagnosed before age 50 years.1 Although this approach is fairly specific in identifying families with highly penetrant LS, it is also overly restrictive and does not consider the possibility of later-onset variants of the disease, the implications of extracolonic tumors, or the limitations imposed by small family size.

Many families with known LS do not meet the original Amsterdam criteria, and this approach misses many families because of poor sensitivity. Therefore, it has been suggested, given the availability of an immunohistochemistry-based screening test for mismatch repair that closely mimics phenotypic microsatellite instability, that testing all colorectal (and perhaps endometrial) cancers for loss of proteins associated with mismatch DNA repair deficiency, or all cancers below some age cutoff, may overcome the limitations of selective criteria. However, the effectiveness of such a “universal” approach to screening for LS has not been tested in a population-based manner.

In this issue of JAMA, Moreira and colleagues2 address this question by performing a pooled-data analysis of a large set of population-based patient cohorts from around the world to determine the sensitivity and efficiency of several different strategies for LS screening, including the “universal” approach. Using more than 10 000 CRC samples, the authors found overall that universal tumor testing for mismatch repair deficiency was superior in sensitivity to the Bethesda guidelines, which incorporate personal and family history information, and which have been reported to be more accurate than the Amsterdam criteria,3 or an approach using an age cut-off of 70 years old, but that a hybrid of testing all tumors in individuals 70 years or younger and in older patients who meet Bethesda guidelines provides a reasonable compromise that may result in substantial cost savings.

The study by Moreira et al2 confirms that the prevalence of LS is high enough among patients with CRC, 3.1% in the whole series, that screening should be considered. However, in the EPICOLON cohort, consisting of patients newly diagnosed with CRC in 20 community hospitals in Spain,3 the prevalence was only 0.9% compared with 2.9% to 3.5% in the other 3 cohorts analyzed. The current study does not address possible explanations for this difference. Some patients in the study by Moreira et al were not drawn from a population-based registry but were excluded from analyses on the performance characteristics of screening strategies. Because most germline tests were driven by abnormal tumor testing results and not all patients underwent “gold-standard” (germline) testing, the high sensitivity estimates for screening strategies are probably somewhat optimistic. In addition, the PMS2 gene was not tested in many patients, so some persons with PMS2 mutations were probably missed. In this study, microsatellite instability testing added little to immunohistochemistry, but not all previous studies have found similar results. Selective BRAF mutation testing or promoter methylation testing to identify sporadic CRC were not performed, but the focus of the study was on the sensitivity of screening strategies, not specificity.

These results highlight the limitations of various clinical criteria to identify persons with LS, particularly those with mutations in the MSH6 or PMS2 genes. The study results should remind clinicians that simply asking about a family history of CRC in a first-degree relative will miss the majority of patients with LS: only 43% of patients with LS had such a family history—approximately 50% of those with MLH1 and MSH2 gene mutations and less than 20% of those with MSH6 and PMS2 gene mutations. Furthermore, although the mean age at CRC diagnosis was 48 years in LS patients, only 45% were diagnosed with CRC at 50 years or younger.

The potential for individualized preventive medicine provides the rationale for screening for LS. In deciding whether to establish widespread screening for LS in selected subgroups, the same considerations that govern screening for CRC in the general population could be applied. The target condition must be common enough to justify screening. A long asymptomatic period must allow for effective interventions. The potential benefits must outweigh the risks. The aggregate costs of screening and its consequences must be acceptable.

Moreira et al2 confirm that a variety of strategies can identify a significant number of persons with LS among patients with CRC. The benefits of intensive CRC and adenoma screening and prophylactic hysterectomy-oophorectomy in LS are well established.4 – 7 This raises several questions. What is the balance between the potential benefits and harms of screening? Are the economic costs acceptable? Which screening strategies are preferred?

Several studies have addressed the potential psychological harms of testing for LS. These studies include select populations and are observational. Patients considering genetic testing can develop short-term increases in anxiety, distress, and fear of cancer or death, especially among mutation carriers.8 – 10 Generally, a person’s psychological state returns to baseline after several months. Longer follow-up has demonstrated no major adverse psychological consequences for either mutation carriers or noncarriers after 1 and 3 years.8 – 9 ,11 However, some groups, such as younger men affected by cancer, may be at higher risk for adverse psychological effects.12 Patients may express fear concerning discrimination in employment or health insurance. In the United States, patients may be counseled that such discrimination is illegal under the Genetic Information Nondiscrimination Act.13

In the absence of controlled studies evaluating the long-term consequences of different screening strategies for LS, computerized decision analytic modeling can be used to explore critical questions. Several modeling studies with long-term time horizons have suggested that screening for LS among persons with CRC is likely to be cost-effective.14 – 17 The same may apply to women with endometrial cancer.18 One study that incorporated the potential short-term adverse effects LS testing can have on quality of life19 found that the long-term gains in life expectancy are likely to outweigh any short-term decreases in quality of life, at acceptable costs.20

Key issues raised by the results of Moreira et al2 were explored in a modeling study.17 Moreira et al found a relatively small incremental yield of universal tumor screening vs a highly sensitive selection strategy based on clinical criteria. The modeling study suggested that tumor testing strategies are likely to be costly compared with clinical criteria strategies when both are implemented optimally.17 However, in the model, when the clinical criteria strategies failed to be implemented in as few as 15% of patients, tumor testing strategies became cost-effective. In clinical practice, routine testing of tumors in pathology laboratories may be more feasible than ensuring widespread application of clinical criteria.

Moreira et al2 address the important issue of age at CRC diagnosis as a factor to inform screening strategies. The modeling study17 estimated that immunohistochemistry-based tumor testing in all persons vs only in those 70 years and younger could be considered cost-effective depending on society’s willingness to pay for preventive services. Using the actual age distribution at CRC diagnosis in the study of Moreira et al, instead of the model’s original assumptions, would result in enhanced cost-effectiveness for the “universal” approach.

Lynch syndrome affects families, not only individuals. Patients often identify the potential benefits to their family, especially their children, as a motivating force driving acceptance of genetic testing.21 However, the published uptake rates for genetic testing among relatives at risk have varied from 34% to 52%.22 – 23 The number of relatives unaffected by cancer but at risk for LS who undergo genetic testing is a key determinant of the cost-effectiveness of any screening strategy.16 – 17 Future public health efforts must address this critical factor.

A recent survey of US hospitals reported that routine tumor testing with immunohistochemistry, microsatellite instability, or both is currently performed at 71% of National Cancer Institute comprehensive cancer centers, 36% of American College of Surgeons–accredited community hospital comprehensive cancer programs, but only 15% of community hospital cancer programs.24 Routine tumor testing with immunohistochemistry or microsatellite instability does not require written consent. The authors suggested that this approach to testing may reflect an emerging standard of care. Routine tumor testing programs require mechanisms to track results, contact patients in ways patients will accept, and facilitate consultation with genetics professionals. Those dealing with results must understand complicating factors, including variants of uncertain significance, and must handle difficult cases, such as patients with classic family pedigrees in whom no mutation is found by current methods.

In the not too distant future, advances in genomic sequencing will challenge current genetic testing approaches. Commercial panels of “cancer genes” are already emerging. With the anticipated further reductions in the costs of DNA sequencing, up-front germline testing at the time of CRC diagnosis could become the most cost-effective strategy to screen for LS.17 Such testing would require written informed consent. Population-based genomic profiling could revolutionize the approach to identifying persons with LS.

The majority of patients with CRC do not have LS. But in the haystack of patients with CRC, those with LS are more like large knitting needles than tiny sewing needles—and a systematic search can find them. The investments of effort and resources required for this search can be rewarded by reductions in cancer incidence and mortality that are possible among patients and their unsuspecting relatives.

Abstract

Context Lynch syndrome is the most common form of hereditary colorectal cancer (CRC) and is caused by germline mutations in DNA mismatch repair (MMR) genes. Identification of gene carriers currently relies on germline analysis in patients with MMR-deficient tumors, but criteria to select individuals in whom tumor MMR testing should be performed are unclear.

Objective To establish a highly sensitive and efficient strategy for the identification of MMR gene mutation carriers among CRC probands.

Design, Setting, and Patients Pooled-data analysis of 4 large cohorts of newly diagnosed CRC probands recruited between 1994 and 2010 (n = 10 206) from the Colon Cancer Family Registry, the EPICOLON project, the Ohio State University, and the University of Helsinki examining personal, tumor-related, and family characteristics, as well as microsatellite instability, tumor MMR immunostaining, and germline MMR mutational status data.

Main Outcome Measures Performance characteristics of selected strategies (Bethesda guidelines, Jerusalem recommendations, and those derived from a bivariate/multivariate analysis of variables associated with Lynch syndrome) were compared with tumor MMR testing of all CRC patients (universal screening).

Results Of 10 206 informative, unrelated CRC probands, 312 (3.1%) were MMR gene mutation carriers. In the population-based cohorts (n = 3671 probands), the universal screening approach (sensitivity, 100%; 95% CI, 99.3%-100%; specificity, 93.0%; 95% CI, 92.0%-93.7%; diagnostic yield, 2.2%; 95% CI, 1.7%-2.7%) was superior to the use of Bethesda guidelines (sensitivity, 87.8%; 95% CI, 78.9%-93.2%; specificity, 97.5%; 95% CI, 96.9%-98.0%; diagnostic yield, 2.0%; 95% CI, 1.5%-2.4%; P < .001), Jerusalem recommendations (sensitivity, 85.4%; 95% CI, 77.1%-93.6%; specificity, 96.7%; 95% CI, 96.0%-97.2%; diagnostic yield, 1.9%; 95% CI, 1.4%-2.3%; P < .001), and a selective strategy based on tumor MMR testing of cases with CRC diagnosed at age 70 years or younger and in older patients fulfilling the Bethesda guidelines (sensitivity, 95.1%; 95% CI, 89.8%-99.0%; specificity, 95.5%; 95% CI, 94.7%-96.1%; diagnostic yield, 2.1%; 95% CI, 1.6%-2.6%; P < .001). This selective strategy missed 4.9% of Lynch syndrome cases but resulted in 34.8% fewer cases requiring tumor MMR testing and 28.6% fewer cases undergoing germline mutational analysis than the universal approach.

Conclusion Universal tumor MMR testing among CRC probands had a greater sensitivity for the identification of Lynch syndrome compared with multiple alternative strategies, although the increase in the diagnostic yield was modest.

via JAMA Network | JAMA: The Journal of the American Medical Association | Identification of Lynch Syndrome Among Patients With Colorectal CancerLynch Syndrome and Colorectal Cancer.

ESMO Consensus Guidelines for management of patients with colon and rectal cancer. A personalized approach to clinical decision making


English: Original Logo of the Society

English: Original Logo of the Society (Photo credit: Wikipedia)

Colorectal cancer (CRC) is the most common tumour type in both sexes combined in Western countries. Although screening programmes including the implementation of faecal occult blood test and colonoscopy might be able to reduce mortality by removing precursor lesions and by making diagnosis at an earlier stage, the burden of disease and mortality is still high. Improvement of diagnostic and treatment options increased staging accuracy, functional outcome for early stages as well as survival. Although high quality surgery is still the mainstay of curative treatment, the management of CRC must be a multi-modal approach performed by an experienced multi-disciplinary expert team. Optimal choice of the individual treatment modality according to disease localization and extent, tumour biology and patient factors is able to maintain quality of life, enables long-term survival and even cure in selected patients by a combination of chemotherapy and surgery. Treatment decisions must be based on the available evidence, which has been the basis for this consensus conference-based guideline delivering a clear proposal for diagnostic and treatment measures in each stage of rectal and colon cancer and the individual clinical situations. This ESMO guideline is recommended to be used as the basis for treatment and management decisions.

3 Diagnosis, management and counselling of hereditary colorectal cancer

All patients with CRC should have a collection of family history regarding polyps and any type of cancer (at least first and second-degree relatives) [V, A]. About 5% of CRC are of hereditary origin. If a clinical suspicion of polyposis or Lynch syndrome is made, the patient should be referred to a specialist in human genetics [V, C]. Average-risk populations should have an organized access to population-CRC screening, if resources are available at national level [V, A]. Methodology and choice of screening modality is a matter of discussion. An overview of management of hereditary CRC syndromes is summarized in Table 2.

View this table:

Table 2.

Management of hereditary colorectal cancer

3.1 Lynch syndrome

Clinical suspicion is based on fulfilment of clinical criteria (Amsterdam, Bethesda) or on an altered molecular screening [microsatellite instability (MSI) and/or immunohistochemistry (IHC) for mismatch repair proteins (MMR)] in the context of a suggestive personal or family history [III, B].

3.1.1 Detection of mutation

Germline genetic testing will be performed according to the results of molecular screening (MSI and/or IHC of MMR). If a tumour block is not available, the gene-specific prediction models may help to guide a genetic strategy [III, B].

If loss of MLH1 expression is observed (especially in non-familial cases), somatic hypermethylation of the MLH1 promoter should be considered, which can be ruled out by testing the somatic BRAF V600E mutation or analysis of hypermethylation of the MLH1 promoter [III, B].

Full germline genetic testing should include DNA sequencing and large rearrangement analysis of the MMR genes [I, A]. Adequate pre- and post-test genetic counselling should always be performed.

3.1.2 Surveillance for healthy mutation carriers

For individuals with Lynch syndrome carrying an MLH1 or MSH2 mutation, colonoscopy should start at the age of 20–25 years and should be repeated every 1–2 years [II, A].

No specific upper limit for surveillance endoscopies is established and it should be based on the individual’s health status.

For healthy individuals with Lynch syndrome carrying an MSH6 or PMS2 mutation, colonoscopy should start at the age of 30 years and be repeated every 1–2 years. Again, no specific upper limit is established [II, A].

Endometrial and ovarian cancer screening may be performed on a yearly basis starting at the age of 30–35 years with gynaecological examination, pelvic ultrasound, analysis of CA125 and aspiration biopsy [IV, C]. Pros and cons should be adequately discussed with the individual subject at risk given the evidence of benefit only from observational studies.

Surveillance for other Lynch-associated cancers is recommended on the basis of the family history and may include upper endoscopy, abdominal ultrasound and urine cytology from the age of 30–35 years in a 1–2-year interval [IV, C].

3.1.3 Chemoprevention

Neither specific chemoprevention nor specific dietary interventions is being recommended at the current time in individuals with Lynch syndrome to prevent CRC, although data are emerging supporting the use of aspirin [7] [II, B].

3.1.4 Risk reduction: prophylactic surgical options

Prophylactic colectomy in healthy mutation carriers is not recommended. Prophylactic gynaecological surgery might be an option in female carriers from the age of 35 onwards and after childbearing is completed [IV, C].

3.1.5 Cancer treatment

The need for intensive surveillance after surgery versus the option of an extended colectomy should be discussed at the time of diagnosis of an advanced adenoma or CRC, especially in young patients [IV, C]. For female CRC patients with good prognosis, surveillance/surgical options for gynecological cancer should also be discussed. Chemotherapy regimens are the same as those for sporadic CRC.

3.2 Familial colorectal cancer × syndrome

Relatives of individuals with CRC who fulfil the Amsterdam criteria and who do not exhibit MMR deficiency have a moderate risk of CRC. Surveillance would include colonoscopy at a 3–5-year interval, starting 5–10 years before the youngest case in the family. Surveillance of extra-colonic cancers is not recommended.

3.3 FAP

Clinical diagnosis of classical familial adenomatous polyposis (FAP) is based on the identification of >100 colorectal adenomas. Lifetime risk of development of CRC is 100%.

3.3.1 Attenuated FAP

Clinical diagnosis of attenuated FAP is based on the following criteria:

  • at least two patients with 10–99 adenomas at age >30 years; or

  • one patient with 10–99 adenomas at age >30 years, a first-degree relative with CRC and few adenomas and no family members with >100 adenomas before the age of 30 years.

3.3.2 Genetics

Genetic testing (germline adenomatous-polyposis-coli (APC) mutation) should start by investigating the affected individual. If the causative mutation is detected, pre-symptomatic diagnosis can be offered to at-risk family members. When the causative mutation is not identified, all at-risk family members should undergo colorectal endoscopic screening [V, C].

3.3.3 Colorectal screening

In families with classic FAP, flexible sigmoidoscopy is an adequate technique and it should be performed every 2 years, starting at the age of 12–14 years, and continued lifelong in mutation carriers [V, C]. If adenomas are found, colonoscopy should be done annually until colectomy.

In families without an identified APC mutation, surveillance should be performed every 2 years until the age of 40, and be repeated every 3–5 years between 40 and 50 years and may continue with general screening at age 50 if no polyposis has developed [V, C]. When an attenuated form is suspected, total colonoscopy is needed. In this setting, examination should be performed every 2 years until polyposis is diagnosed. Screening should be started at the age of 18–20 years and continued lifelong.

3.3.4 Screening for extra-colonic manifestations

It should start when colorectal polyposis is diagnosed or at the age of 25–30 years, whichever comes first [V, C].

Gastroduodenal endoscopy should be performed every 5 years until adenomas are detected [V, C]. Screening for thyroid cancer should be performed by annual sonography of the neck [V, C]. Regular physical examination and if indicated abdominal CT should be performed in search for desmoid tumours [V, C]. Screening for other extra-colonic manifestations is not justified because of their low prevalence and/or limited clinical impact. Since gastrointestinal adenomas may also develop in the jejunum and ileum, it has been suggested that regular screening by barium contrast series or wireless capsule endoscopy could be performed [V, C].

3.3.5 Treatment

Surgical resection is the standard of care in patients with classical FAP [IV, A]. It can be considered in some patients with an attenuated form. Surgical resection includes either total colectomy with ileoanal pouch anastomosis or subtotal colectomy with ileorectal anastomosis, once adenomas are detected [IV, C]. Duodenal adenomas are managed with endoscopic polypectomy, and in Spigelman stage IV (see below), duodenal–pancreatectomy may be considered. Because of the high recurrence rate of desmoid tumours, surgical resection should be delayed unless complications occur. The first-line treatment in patients with large or growing intra-abdominal or abdominal wall desmoid tumours is based on, e.g COX 2 inhibitors, tamoxifen and tyrosine kinase inhibitors.

3.3.6 Surveillance for healthy mutation carriers

Colon-rectum

Regular endoscopic surveillance every 6–12 months after subtotal colectomy is recommended to detect rectal adenoma recurrence [V, C]. When total colectomy is performed, surveillance of the pouch can be repeated every 1–2 years. In patients with attenuated FAP conservative management with endoscopic polypectomy, examination of the entire colon and rectum should be performed annually [V, C].

Duodenum

Surveillance of duodenal manifestation will depend on its extension. When it corresponds to Spigelman stage I or II, upper endoscopy should be performed every 5 or 3 years, respectively, and every 1–2 years in stage III or every 6 months in stage IV [IV, C].

3.4 MUTYH-associated polyposis

MUTYH-associated polyposis (MAP) is inherited as an autosomal recessive trait with high penetrance. Clinically, MAP resembles the attenuated form of FAP syndrome, with an average age of onset around the mid-50s with often <100 adenomas and, accordingly, patient management is very similar.

3.4.1 Screening for family members

Individuals should undergo total colonoscopy every 2 years, starting at the age of 18–20 years and continuing lifelong [V, C]. Genetic testing allows the most cost-effective screening to be performed by focussing colorectal examinations only on gene carriers. However, when the causative mutation is not identified, all at-risk family members should undergo colorectal screening.

3.4.2 Treatment for healthy gene carriers

Colorectal management is similar to that proposed for patients with attenuated FAP.

ESMO Consensus Guidelines for management of patients with colon and rectal cancer. A personalized approach to clinical decision making

Table 2.

Management of hereditary colorectal cancer

Syndrome Diagnosis of index case (with cancer) Management of the affected individual (with cancer) Management of individuals at high risk (healthy mutation carriers or individuals at 50% risk of being mutation carrier)
Clinical Molecular screening (tumour tissue) Germline genetic testing (blood) Treatment Follow-up Cancer risk Surveillance Germline genetic testing (blood)
Lynch Amsterdam, Bethesda MSI and/or IHC for MMR proteins MLH1, MSH2
MSH6, PMS2
  • Tumour resection

  • Discuss colectomy, especially in young patients

Yearly endoscopy of the remnant colon or rectum High
  • Colonoscopy q 1–2 years, starting age 25 (30 years in case of MSH6 or PMS2 mutations)

  • Annual pelvic examinations, transvaginal ultrasound, ca125, endometrial biopsy in females, starting age 30–35 years

Direct genetic testing of the mutation identified in the family
Familial CRC X Amsterdam, Bethesda No MMR deficiency Unknown As average population As average population Moderate only CRC
  • Colonoscopy 1 3–5 years, starting 5–10 years before youngest case in the family.

None
FAP Colonoscopy: >100 adenomas none APC
  • Total or subtotal colectomy when adenomas occur

  • Endoscopic removal of duodenal adenomas

  • After subtotal colectomy: rectal examination q 6–12 m

  • After total colectomy: pouch exam. q 1–2 years

  • Duodenoscopy from 6 months to 5 years according to Spigelman stage

  • Thyroid examination yearly

100%
  • Flexible sigmoidoscopy q 2 years, starting age 12–14 years until diagnosis of adenomas

  • If no mutation identified in the family: Flexible sigmoidoscopy q 2 years until 40 years, then q 3–5 years until 50, then general population screening

APC
Attenuated FAP (aFAP) Colonoscopy:

  1. 2 relatives 10–99 adenomas (>30 years of age)

  2. 1 relative of CRC patient with 10–99 adenomas (>30 years of age)

APC
  • Total or subtotal colectomy when adenomas occur.

  • Endoscopic removal of duodenal adenomas

As above High
  • Colonoscopy q 2 years, starting age 18–20 years, lifelong in mutation carriers.

APC
MAP As aFAP MUTYH As aFAP As aFAP High As aFAP MUTYH
  • APC, adenomatous-polyposis-coli; MSI, microsatellite instability; MMR, mismatch repair proteins; CRC, colorectal cancer; FAP, familial adenomatous polyposis; aFAP, attenuated FAP; MAP, MUTYH-associated polyposis.

via ESMO Consensus Guidelines for management of patients with colon and rectal cancer. A personalized approach to clinical decision making.

Inherited predisposition to colorectal cancer in patients without multiple polyps


 

Lynch Syndrome / Hereditary non-polyposis colorectal cancer (HNPCC) and related syndromes

Lynch Syndrome (also known as Hereditary non-polyposis colorectal cancer(HNPCC; OMIM 120435)) accounts for approximately 2.2-4% of all colorectal cancer (Hampel et al. 2005).  Lynch Syndrome is a familial cancer syndrome which accounts for approximately 2-3% of all colorectal cancer in the UK.  It has formerly been known as Hereditary Non-Polyposis Colorectal Cancer Syndrome (HNPCC), however the phenotype is more complex with multiple extracolonic tumours, for example, so this term has now been largely abandoned.

An Irish family tree with Lynch Syndrome caused by an inherited mutation in MSH2.  Members of this family are affected predominantly with colorectal cancer (CRC), but also small bowel cancer (SBCa), Gastric, Pancreatic, Uterine and other cancers, as well as conditions not linked to Lynch Syndrome such as Crohn’s disease.

LS is an autosomally dominant inherited condition commonly caused by germline mutation in one of four DNA mismatch repair genes, MLH1, MSH2, MSH6 and PMS2.  A minority of these families may be identified because they have multiple affected members diagnosed at an early age.   The Amsterdam Criteria I and II (Vasen et al. 1993; Vasen et al. 1999)(see below) identify patients for colonoscopic and other screening.  Approximately 40-80% of patients meet these criteria, with 50% of the remainder meeting the modified criteria which include extracolonic cancers.  The revised Bethesda criteria (Umar et al. 2004) are used to identify patients for molecular screening of HNPCC, i.e. microsatellite instability ± immunohistochemistry studies.  Approximately 80% of patients are identified using the Bethesda criteria, although the specificity is low.

Immunohistochemistry and microsatellite instability analysis for Lynch Syndrome

Amsterdam I Criteria

  • ≥3 1st degree relatives with colorectal cancer (CRC)
  • ≥2 generations affected
  • One family member below age 50 years of age
  • Exclude familial adenomatous polyposis

Amsterdam II Criteria

  • As for Amsterdam I except that CRC may be substituted by cancer of endometrium, small bowel, or pelviureter.

Most families with LS, however, do not fulfil the Amsterdam criteria. The Revised Bethesda criteria are another set of diagnostic criteria designed to increase the diagnostic yield of testing for LS [7]. For example, all individuals diagnosed under the age of 50 years should be tested for the molecular features of LS in their tumours.  If molecular testing is diagnostic of LS, it can subsequently determine which families should undergo colonoscopic and other investigations, and to screen other high risk family members. The Revised Bethesda guidelines are designed to streamline the clinical diagnostic pathways used to identify mutation carriers in patients with colorectal cancer who might or might not fulfil the Amsterdam criteria, thus increasing diagnostic yield screening for LS.

The identification of such families with Lynch syndrome involves an extensive diagnostic work up comprising various screening tools combined with genetic and immunohistochemical tests.  Initially the tumour from an affected individual may be tested for features suggestive of this condition by either immunohistochemistry of the mismatch repair proteins and/or DNA microsatellite instability (a hallmark of faulty DNA mismatch repair).  If either of these tests are abnormal, then germline testing may be performed to identify a putative heritable mutation in one of the causative genes.

Patient selection using Amsterdam and revised Bethesda criteria have been applied to clinical pathways in the United Kingdom through the use of national guidelines.  Given the implication of family history and known mortality benefit, the early recognition of Lynch syndrome is highly desirable. There have been concerns over the sensitivity, specificity, and predictive value of already existing guidelines. About 22% of affected individuals do not fulfil either Amsterdam or the Revised Bethesda criteria. As Barnetson et al argues, there might be multiple reasons for this such as small family size, unknown or inadequately taken family history, adoption, and patients without available tumour data [9]. A number of alternative screening models have been developed, such as MMRpredict, PREMM 1,2,6, MMRPro, and MsPath whilst searching for a careening tool that is simple, accurate, and clinically useful for predicting the likelihood of Lynch Syndrome.

Bethesda (revised) Criteria (Umar et al 2003)

  • 1 CRC below age 50 yr
  • Multiple CRC or HNPCC-related cancers
  • CRC with MSI-related histology under 60 years of age
  • CRC or HNPCC-related cancer in ≥1 1st degree relative, < 50 years of age
  • CRC or HNPCC-related cancer in at least two 1st or 2nd degree relatives, any age

MSI-type Histology: Using the revised Bethesda Criteria patients aged 50-60 years should have tumour testing

There is a slight preponderance of right-sided tumours (70% proximal to the splenic flexure) in Lynch Syndrome.  It is a highly penetrant condition which also features extracolonic cancers such as endometrial and gastric cancer.  The adenoma to carcinoma sequence is rapid with interval cancers occurring in 5% of patients despite two-yearly colonoscopic surveillance (Jarvinen, Aarnio et al. 2000).  The tumours are characteristically associated with a local lymphocytic infiltrate and a good prognosis when surgically resected (Jass 2000; Takemoto et al. 2004).

Screening tumours for Lynch Syndrome – is it cost effective?

There are clinical and economic trade-offs when implementing screening protocol on a large scale. As nondirected germline mutation testing for Lynch syndrome is prohibitively expensive at £1000 per gene, MSI and IHC are the screening tests of choice. In view of high costs of testing of all colorectal cancers for MSI or loss or MMR protein, an approach described by Heather Hampel of The Ohio State University, the Revised Bethesda Guidelines were felt to be an appropriate tool to select patients for genetic testing. However, the question remains open: is the “reflex” molecular tumour testing justified clinically and economically? Kastrinos et al, have looked into the popularity of the universal testing across several centres in US. Unsurprisingly, a pessimistic picture emerged showing the low uptake of the concept. The benefits of the universal testing are counterbalanced by practical problems such as an informed consent controversy, practicalities of dealing with the complexity of test results and the resultant implications. The fact that the cost effectiveness of this approach has not been yet validated plays heavily against such approach.

In US, Ramsey et al have carried out a study looking at cost-effectiveness of different strategies for identifying of persons with Lynch syndrome. The average cost per carrier detected using Bethesda guidelines was $15,787, and expanding this strategy to include costs and benefits for first degree relatives greatly improves the cost effectiveness of the program. Expanding the program to first degree relatives leads to savings from intensive screening to exceed the cost of testing.

In Europe, Pinol et al, has carried out a similar study evaluating cost-minimization analysis of identification strategies for MSH2/MLH1-associated Lynch syndrome. Authors concluded that clinical selection of patients using the Revised Bethesda Guidelines followed by either MSI analysis (€11,989 per detected mutation) or IHC (€10,644 per detected mutation) has proved to be more cost effective than performing any of these tests directly (€32,140 and €37,956 per detected mutation, respectively).

Further research has been carried out by Dinh et al in 2010 looking at the cost effectiveness of MMR gene mutations screening, and reached the conclusion that it is comparable to that of already established cancer screening protocols such as colorectal, cervical, and breast cancer screening. Authors argue that primary screening of individuals for MMR gene mutations, starting with the risk assessment between the ages of 25 and 35, followed by genetic testing of those whose risk exceeds 5%, is a strategy that could improve health outcomes in a cost effective manner relative to current practise with the average cost-effectiveness ratio of $26,000 per QALY.

These results echo several European studies, such as that carried out by Pinol V et al, 2005 in Spain, where authors suggest that MSI and IHC testing are equivalent strategies in terms of cost effectiveness when it comes to screening selected patients for MMR mutations

Large bowel surveillance for Lynch syndrome family members and gene carriers

Total colonic surveillance (at least biennial) should commence at age 25 years. Surveillance colonoscopy every 18 months may be appropriate because of the occurrence of interval cancers in some series.  Surveillance should continue to age 7075 years or until co-morbidity makes it clinically inappropriate. If a causative mutation is identified in a relative and the consultand is a non-carrier, surveillance should cease and measures to counter general population risk should be applied.

The effectiveness of colonoscopic surveillance for people with MMR gene mutations and Lynch family members has been examined in retrospective casecontrol comparisons. Screened individuals were compared to control subjects who declined, or did not receive, regular colonoscopy with respect to outcomes of cancer incidence, tumour stage and mortality, or mortality alone. Surveillance appears to provide an average of 7 years of extra life for Lynch syndrome family members.  Thus, available evidence supports regular colonoscopic surveillance as a means of early colorectal cancer detection, leading to mortality reduction as well as reduction in cancer incidence.

Surveillance should consist of total colonoscopy, since the risk of polyps and cancer is high and a substantial proportion of patients have neoplasia restricted to the proximal colon.  Colonoscopy is preferable to flexible sigmoidoscopy combined with barium enema. Because the cancer risk is high, it is not appropriate to accept an incomplete colonoscopy until the next surveillance interval. Incomplete colonoscopy should be followed soon after, or even the same day, by completion CT colonography in centres skilled in providing this technique to a high quality, but repeated radiation exposure should be avoided wherever possible. Repeat full colonoscopy or barium enema remain as options. Chromoendoscopy and narrow wavelength visible light (narrow band) endoscopy may have a place in the detection of small or flat lesions, but there is very limited experience and evidence is restricted to descriptive studies of their use in Lynch syndrome surveillance. Hence, the utility of such techniques requires further assessment and is neither recommended nor discouraged in high risk surveillance, but should not replace conventional endoscopic approaches. Evidence for commencing surveillance at 25 years of age is based on observational data that indicate that the risk increases substantially from age 25 in groups defined by family history and in groups defined by presence of a mutation.

Colorectal resection has a place as prophylaxis and for established cancer in Lynch syndrome family members and/or MMR gene carriers.

Patients who have developed a colorectal malignancy and who come from a Lynch syndrome family, or carry a mutation in an MMR gene, should be counselled and offered a surgical procedure that includes both a cancer control element and prophylaxis to counter future cancer risk. At present there is no evidence to guide decision-making on primary prophylactic surgery for patients who do not yet have cancer.

People with MMR gene mutations or those from Amsterdam positive Lynch syndrome families who have cancer will require surgery unless treatment is palliative. Case series evidence shows that the risk of metachronous colorectal cancer is high following segmental resection (16%), but substantially lower after colectomy and ileorectal anastomosis (3%).  Hence, incorporating a prophylactic element to the cancer resection is appropriate. For patients with proximal tumours, colectomy and ileorectal anastomosis is most relevant, but the retained rectum must be screened because cancer risk in the retained rectum is 3% every 3 years for the first 12 years.

Upper gastrointestinal surveillance for Lynch syndrome family members and/or MMR gene carriers

In families manifesting gastric cancer as part of the phenotype, biennial upper gastrointestinal endoscopy should be considered. The evidence is limited and a pragmatic recommendation is to screen from age 50 since the incidence is very low until that age. Surveillance should continue to age 75 or until the causative mutation in that family has been excluded. This recommendation is based on observations that some Lynch syndrome families have a particular propensity for gastric cancer.  There is as yet no evidence that this reduces mortality.

Other non-polyposis predisposition to colorectal neoplasia

About 15% of sporadic colorectal cancers are also microsatellite unstable and feature loss of protein staining on immunohistochemistry but are not caused by germline mutations in mismatch repair genes.  Often they are acquired sporadic type cancers caused by methylation of MLH1.  These associated with a particular genetic pathway which differs from HNPCC by the presence of BRAF V600E mutations, the absence of β-CATENIN exon 3 mutations and a methylator genotype (Young et al. 2005) (Oliveira et al. 2005).  Recently kindreds demonstrating some inheritance of MLH1 promoter methylation have been identified (Suter et al. 2004; Hitchins, Williams et al. 2005), although the evidence for this inherited epimutation is limited to a few case studies and may be related in imprinting (Chong et al. 2007; Hitchins and Ward 2007).

In addition there are a number of families which fulfil Amsterdam criteria but do not demonstrate microsatellite instability (Dove-Edwin, de Jong et al. 2006).  These families are termed by one group familial colorectal cancer type X (Lindor et al. 2005), and have a lower incidence of colorectal cancer occurring at a later age.  The genetic aetiology is not known for these families.

Approximately 93% of colorectal cancer occurs after the age of 50 years, and thus those young patients who develop cancer are likely to have an inherited or other risk factor such as chronic colitis.  The genetic risk is partially made up by inherited mutations which cause HNPCC.  However, there are likely to be a number of other lower penetrance genes which cause cancer predisposition, many of which may have a recessive form of inheritance and few polyps, and therefore a less clearly identifiable phenotype.

 

Lynch Syndrome and other non-polyposis inherited cancer syndromes


Lynch Syndrome / Hereditary non-polyposis colorectal cancer (HNPCC) and related syndromes

Lynch Syndrome (OMIM 120435)) is a familial cancer syndrome which accounts for approximately 2.2-4% of all colorectal cancer in the USA (Hampel et al. 2005) and 2-3% of the total in the UK.  It was also known as Hereditary Non-Polyposis Colorectal Cancer Syndrome (HNPCC), however the phenotype is more complex with multiple extracolonic tumours, for example, so this term has now been largely abandoned.

An Irish family tree with Lynch Syndrome caused by an inherited mutation in MSH2.  Members of this family are affected predominantly with colorectal cancer (CRC), but also small bowel cancer (SBCa), Gastric, Pancreatic, Uterine and other cancers, as well as conditions not linked to Lynch Syndrome such as Crohn’s disease.

LS is an autosomally dominant inherited condition commonly caused by germline mutation in one of four DNA mismatch repair genes, MLH1, MSH2, MSH6 and PMS2, involved with the mismatch repair (MMR) pathway. This pathway functions to identify and remove single nucleotide mismatches or insertions and deletion loops. Mutations in four of the MMR genes can cause Lynch syndrome [Peltomaki 2003]. The functions of the mismatch repair genes can be disrupted by missense mutations, truncating mutations, splice site mutations, large deletions, or genomic rearrangements. In addition, germline deletion within EPCAM, which is not an MMR gene, can disrupt the MMR pathway. EPCAM deletions result in inactivating the adjacent MMR gene MSH2, even though MSH2 itself has not been mutated.

Identification of LS Families

A minority of Lynch Syndrome families may be identified because they have multiple affected members diagnosed at an early age.   The Amsterdam Criteria I and II (Vasen et al. 1993; Vasen et al. 1999)(see below) identify patients for colonoscopic and other screening.  Approximately 40-80% of patients meet these criteria, with 50% of the remainder meeting the modified criteria which include extracolonic cancers.  The revised Bethesda criteria (Umar et al. 2004) are used to identify patients for molecular screening of HNPCC, i.e. microsatellite instability ± immunohistochemistry studies.  Approximately 80% of patients are identified using the Bethesda criteria, although the specificity is low.

Immunohistochemistry and microsatellite instability analysis for Lynch Syndrome

Amsterdam I Criteria

  • ≥3 1st degree relatives with colorectal cancer (CRC)
  • ≥2 generations affected
  • One family member below age 50 years of age
  • Exclude familial adenomatous polyposis

Amsterdam II Criteria

  • As for Amsterdam I except that CRC may be substituted by cancer of endometrium, small bowel, or pelviureter.

Most families with LS, however, do not fulfil the Amsterdam criteria. The Revised Bethesda criteria are another set of diagnostic criteria designed to increase the diagnostic yield of testing for LS [7]. For example, all individuals diagnosed under the age of 50 years should be tested for the molecular features of LS in their tumours.  If molecular testing is diagnostic of LS, it can subsequently determine which families should undergo colonoscopic and other investigations, and to screen other high risk family members. The Revised Bethesda guidelines are designed to streamline the clinical diagnostic pathways used to identify mutation carriers in patients with colorectal cancer who might or might not fulfil the Amsterdam criteria, thus increasing diagnostic yield screening for LS.

The identification of such families with Lynch syndrome involves an extensive diagnostic work up comprising various screening tools combined with genetic and immunohistochemical tests.  Initially the tumour from an affected individual may be tested for features suggestive of this condition by either immunohistochemistry of the mismatch repair proteins and/or DNA microsatellite instability (a hallmark of faulty DNA mismatch repair).  If either of these tests are abnormal, then germline testing may be performed to identify a putative heritable mutation in one of the causative genes.

Patient selection using Amsterdam and revised Bethesda criteria have been applied to clinical pathways in the United Kingdom through the use of national guidelines.  Given the implication of family history and known mortality benefit, the early recognition of Lynch syndrome is highly desirable. There have been concerns over the sensitivity, specificity, and predictive value of already existing guidelines. About 22% of affected individuals do not fulfil either Amsterdam or the Revised Bethesda criteria. As Barnetson et al argues, there might be multiple reasons for this such as small family size, unknown or inadequately taken family history, adoption, and patients without available tumour data [9]. A number of alternative screening models have been developed, such as MMRpredict, PREMM 1,2,6, MMRPro, and MsPath whilst searching for a careening tool that is simple, accurate, and clinically useful for predicting the likelihood of Lynch Syndrome.

Bethesda (revised) Criteria (Umar et al 2003)

  • 1 CRC below age 50 yr
  • Multiple CRC or HNPCC-related cancers
  • CRC with MSI-related histology under 60 years of age
  • CRC or HNPCC-related cancer in ≥1 1st degree relative, < 50 years of age
  • CRC or HNPCC-related cancer in at least two 1st or 2nd degree relatives, any age

MSI-type Histology: Using the revised Bethesda Criteria patients aged 50-60 years should have tumour testing

There is a slight preponderance of right-sided tumours (70% proximal to the splenic flexure) in Lynch Syndrome.  It is a highly penetrant condition which also features extracolonic cancers such as endometrial and gastric cancer.  The adenoma to carcinoma sequence is rapid with interval cancers occurring in 5% of patients despite two-yearly colonoscopic surveillance (Jarvinen, Aarnio et al. 2000).  The tumours are characteristically associated with a local lymphocytic infiltrate and a good prognosis when surgically resected (Jass 2000; Takemoto et al. 2004).

Screening tumours for Lynch Syndrome – is it cost effective?

There are clinical and economic trade-offs when implementing screening protocol on a large scale. As nondirected germline mutation testing for Lynch syndrome is prohibitively expensive at £1000 per gene, MSI and IHC are the screening tests of choice. In view of high costs of testing of all colorectal cancers for MSI or loss or MMR protein, an approach described by Heather Hampel of The Ohio State University, the Revised Bethesda Guidelines were felt to be an appropriate tool to select patients for genetic testing. However, the question remains open: is the “reflex” molecular tumour testing justified clinically and economically? Kastrinos et al, have looked into the popularity of the universal testing across several centres in US. Unsurprisingly, a pessimistic picture emerged showing the low uptake of the concept. The benefits of the universal testing are counterbalanced by practical problems such as an informed consent controversy, practicalities of dealing with the complexity of test results and the resultant implications. The fact that the cost effectiveness of this approach has not been yet validated plays heavily against such approach.

In US, Ramsey et al have carried out a study looking at cost-effectiveness of different strategies for identifying of persons with Lynch syndrome. The average cost per carrier detected using Bethesda guidelines was $15,787, and expanding this strategy to include costs and benefits for first degree relatives greatly improves the cost effectiveness of the program. Expanding the program to first degree relatives leads to savings from intensive screening to exceed the cost of testing.

In Europe, Pinol et al, has carried out a similar study evaluating cost-minimization analysis of identification strategies for MSH2/MLH1-associated Lynch syndrome. Authors concluded that clinical selection of patients using the Revised Bethesda Guidelines followed by either MSI analysis (€11,989 per detected mutation) or IHC (€10,644 per detected mutation) has proved to be more cost effective than performing any of these tests directly (€32,140 and €37,956 per detected mutation, respectively).

Further research has been carried out by Dinh et al in 2010 looking at the cost effectiveness of MMR gene mutations screening, and reached the conclusion that it is comparable to that of already established cancer screening protocols such as colorectal, cervical, and breast cancer screening. Authors argue that primary screening of individuals for MMR gene mutations, starting with the risk assessment between the ages of 25 and 35, followed by genetic testing of those whose risk exceeds 5%, is a strategy that could improve health outcomes in a cost effective manner relative to current practise with the average cost-effectiveness ratio of $26,000 per QALY.

These results echo several European studies, such as that carried out by Pinol V et al, 2005 in Spain, where authors suggest that MSI and IHC testing are equivalent strategies in terms of cost effectiveness when it comes to screening selected patients for MMR mutations

Large bowel surveillance for Lynch syndrome family members and gene carriers

Total colonic surveillance (at least biennial) should commence at age 25 years. Surveillance colonoscopy every 18 months may be appropriate because of the occurrence of interval cancers in some series.  Surveillance should continue to age 7075 years or until co-morbidity makes it clinically inappropriate. If a causative mutation is identified in a relative and the consultand is a non-carrier, surveillance should cease and measures to counter general population risk should be applied.

The effectiveness of colonoscopic surveillance for people with MMR gene mutations and Lynch family members has been examined in retrospective casecontrol comparisons. Screened individuals were compared to control subjects who declined, or did not receive, regular colonoscopy with respect to outcomes of cancer incidence, tumour stage and mortality, or mortality alone. Surveillance appears to provide an average of 7 years of extra life for Lynch syndrome family members.  Thus, available evidence supports regular colonoscopic surveillance as a means of early colorectal cancer detection, leading to mortality reduction as well as reduction in cancer incidence.

Surveillance should consist of total colonoscopy, since the risk of polyps and cancer is high and a substantial proportion of patients have neoplasia restricted to the proximal colon.  Colonoscopy is preferable to flexible sigmoidoscopy combined with barium enema. Because the cancer risk is high, it is not appropriate to accept an incomplete colonoscopy until the next surveillance interval. Incomplete colonoscopy should be followed soon after, or even the same day, by completion CT colonography in centres skilled in providing this technique to a high quality, but repeated radiation exposure should be avoided wherever possible. Repeat full colonoscopy or barium enema remain as options. Chromoendoscopy and narrow wavelength visible light (narrow band) endoscopy may have a place in the detection of small or flat lesions, but there is very limited experience and evidence is restricted to descriptive studies of their use in Lynch syndrome surveillance. Hence, the utility of such techniques requires further assessment and is neither recommended nor discouraged in high risk surveillance, but should not replace conventional endoscopic approaches. Evidence for commencing surveillance at 25 years of age is based on observational data that indicate that the risk increases substantially from age 25 in groups defined by family history and in groups defined by presence of a mutation.

Colorectal resection has a place as prophylaxis and for established cancer in Lynch syndrome family members and/or MMR gene carriers.

Patients who have developed a colorectal malignancy and who come from a Lynch syndrome family, or carry a mutation in an MMR gene, should be counselled and offered a surgical procedure that includes both a cancer control element and prophylaxis to counter future cancer risk. At present there is no evidence to guide decision-making on primary prophylactic surgery for patients who do not yet have cancer.

People with MMR gene mutations or those from Amsterdam positive Lynch syndrome families who have cancer will require surgery unless treatment is palliative. Case series evidence shows that the risk of metachronous colorectal cancer is high following segmental resection (16%), but substantially lower after colectomy and ileorectal anastomosis (3%).  Hence, incorporating a prophylactic element to the cancer resection is appropriate. For patients with proximal tumours, colectomy and ileorectal anastomosis is most relevant, but the retained rectum must be screened because cancer risk in the retained rectum is 3% every 3 years for the first 12 years.

Upper gastrointestinal surveillance for Lynch syndrome family members and/or MMR gene carriers

In families manifesting gastric cancer as part of the phenotype, biennial upper gastrointestinal endoscopy should be considered. The evidence is limited and a pragmatic recommendation is to screen from age 50 since the incidence is very low until that age. Surveillance should continue to age 75 or until the causative mutation in that family has been excluded. This recommendation is based on observations that some Lynch syndrome families have a particular propensity for gastric cancer.  There is as yet no evidence that this reduces mortality.

Other non-polyposis predisposition to colorectal neoplasia

About 15% of sporadic colorectal cancers are also microsatellite unstable and feature loss of protein staining on immunohistochemistry but are not caused by germline mutations in mismatch repair genes.  Often they are acquired sporadic type cancers caused by methylation of MLH1.  These associated with a particular genetic pathway which differs from LS by the presence of BRAF V600E mutations, the absence of β-CATENIN exon 3 mutations and a methylator genotype (Young et al. 2005) (Oliveira et al. 2005).  Recently kindreds demonstrating some inheritance of MLH1 promoter methylation have been identified (Suter et al. 2004; Hitchins, Williams et al. 2005), although the evidence for this inherited epimutation is limited to a few case studies and may be related in imprinting (Chong et al. 2007; Hitchins and Ward 2007).

In addition there are a number of families which fulfil Amsterdam criteria but do not demonstrate microsatellite instability (Dove-Edwin, de Jong et al. 2006).  These families are termed by one group familial colorectal cancer type X (Lindor et al. 2005), and have a lower incidence of colorectal cancer occurring at a later age.  The genetic aetiology is not known for these families.

Approximately 93% of colorectal cancer occurs after the age of 50 years, and thus those young patients who develop cancer are likely to have an inherited or other risk factor such as chronic colitis.  The genetic risk is partially made up by inherited mutations which cause HNPCC.  However, there are likely to be a number of other lower penetrance genes which cause cancer predisposition, many of which may have a recessive form of inheritance and few polyps, and therefore a less clearly identifiable phenotype.

UK BSG/ACPGBI Guidelines for Moderate Risk Family History/Colorectal Cancer Risk Groups


 

BSG/ACPGBI GUIDANCE ON LARGE BOWEL SURVEILLANCE FOR INDIVIDUALS WITH A FAMILY HISTORY INDICATING A MODERATE RISK (2010)

http://www.bsg.org.uk/clinical-guidelines/endoscopy/guidelines-for-colorectal-cancer-screening-and-surveillance-in-moderate-and-high-risk-groups-update-from-2002.html

Executive summary

Dedicated Clinics: Referrals on the basis of family history are best coordinated through centres with a specialist interest, such as regional genetics services or medical/surgical gastroenterology centres. Such centralisation enables audit of family history ascertainment, assigned level of risk, collection of outcome data and research.

Screening Procedure: Total colonoscopy is the preferred mode of surveillance for the moderate risk categories defined here, owing to the propensity for proximal colonic lesions and the opportunity for snare polypectomy. Incomplete colonoscopy should initiate an alternative imaging modality on the same day, such as double-contrast barium enema or CT colonography. A repeat colonoscopy soon after an incomplete examination is acceptable, but success must be assured. However, radiation exposure should be minimised and regular radiological surveillance is not recommended.

High moderate risk group inclusion criteria comprise familial aggregations where affected relatives are first-degree relatives of each other (first-degree kinship) with at least one being a first-degree relative of the consultand. If both parents are affected, these count as being within first-degree kinship:

– Three affected relatives any age in a first-degree kinship (eg, a parent and a blood-related aunt/uncle and/or grandparent), at least one of whom is a first-degree relative of the consultand, or two siblings/one parent or two siblings/one offspring combinations, or both parents and one sibling. However, there should be no affected relative <50 years old, as otherwise the family would fulfil high risk criteria.

– Two affected relatives aged <60 years in a first-degree kinship or mean age of two affected relatives <60 years. At least one relative must be a first-degree relative of the consultand and so this category includes a parent and grandparent, >2 siblings, >2 children or child+sibling. The risk is sufficiently increased to merit low-intensity surveillance comprising 5-yearly colonoscopy between age 50 and age 75 years. Polyps should be snared; adenoma surveillance applies thereafter if a benign neoplasm is confirmed.

Low-moderate risk group. Inclusion criteria are:

– One affected first-degree relative under 50 years old or

– Two affected first-degree relatives, aged 60 or older.

In both high-moderate and low-moderate categories, pathology tumour material from an affected relative may be available to test for Lynch syndrome gene involvement.

Excluding such instances, there is a modest excess risk meriting a single colonoscopy at age 55 (if older at presentation then instigate forthwith), in the lowmoderate group to identify polyp formers. Polyps should be snared; adenoma surveillance applies thereafter if a benign neoplasm is confirmed. If colonoscopy is clear, reassure and discharge with recommendations relevant to population risk (uptake of faecal occult blood test screening in the UK).

Early-onset colorectal cancer (<50 years). The elevation of risk in relatives of an early-onset case is modest. However, the heightened anxiety and emotive nature of cancer in this age group merit special mention because this frequently initiates requests for surveillance. Such cases are covered by the above risk categorisation, but algorithms can also be used to predict whether the affected relative is a carrier of a mutation in a Lynch syndrome gene. These approaches identify affected individuals where tumour immunohistochemistry and/or microsatellite instability analysis could lead to identification of a DNA mismatch repair gene mutation. Bethesda criteria are not discriminatory within this group because all patients fulfil these criteria due to age alone.

Low Risk Group: People with only one affected relative and who do not fulfil any of the above criteria, and do not fulfil high risk criteria, should be reassured and encouraged to avail themselves of population-based screening measures. The low level residual risk over that of the general population should be explained.

Outcome of screening in Moderate Risk Groups (Dove-Edwin et al BMJ 2005)

Advanced neoplasia and age at initial colonoscopy.

Colonoscopic surveillance is effective in preventing colorectal cancer in individuals from families with hereditary non-polyposis colorectal cancer (group 4) and in individuals with a family history of colorectal cancer that does not meet the Amsterdam criteria. However, colonoscopic surveillance in the families at moderate risk seems not indicated until age 45 (or even 50), and this is true even for the relatives of young patients. Furthermore, surveillance intervals of more than five years may be appropriate in individuals with a moderate risk family history (groups 1-3) in whom no advanced pathology is found.

Colonoscopic polypectomy has been shown to decrease the incidence of colorectal cancer in a large cohort study as well as in clinical practice and to decrease both the incidence and mortality of colorectal cancer in individuals with a family history of hereditary non-polyposis colorectal cancer. It is also considered by some to be a safe tool for population screening. Clear guidelines exist for colorectal surveillance in hereditary non-polyposis colorectal cancer families, but guidelines and practices for individuals at moderate risk on the basis of their family history are heterogeneou.

Concerns exist about colonoscopic surveillance in individuals with a moderate risk family history, as some will not be at increased risk. Dunlop et al calculated that if surveillance were offered to individuals aged 30-70 who have two direct relatives affected or one under age 45 then 235 000 individuals would be eligible in the United Kingdom. Even if the age of initiating surveillance is raised, the potential burden on resources is immense. Colonoscopy is associated with a small risk of serious complications, and this may substantially outweigh any benefits in people at low risk.

In this study, only one incident cancer was detected on surveillance in an individual with a moderate risk family history during 9281 person years of follow-up. In families at moderate risk, advanced neoplasia is very rare below the age of 45 and, if not seen initially, it remains uncommon (under age 65) if follow-up colonoscopy is carried out within six years. These findings are important because individuals with a moderate risk family history who are under age 65 with no advanced neoplasia can be considered to be at low risk and extended surveillance intervals may be sufficient. Individuals with a moderate risk family history in whom advanced neoplasia is seen on initial colonoscopy should continue with colonoscopy every three years. The low yield of advanced neoplasia under the age of 45 is true also of those with a first degree relative affected under age 45. Only 4% of 139 individuals in group 1—families with one case of colorectal cancer diagnosed under age 45, and no other cases—screened under age 45 (mean age 33) had an adenoma of any description. Despite the increased risk of colorectal cancer in this group individuals’ absolute risk therefore remains small and the benefit of screening seems minimal below the age of 45.

 

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