Risk of urothelial bladder cancer in Lynch syndrome is increased, in particular among MSH2 mutation carriers

The genetic basis of Lynch syndrome and its implications for clinical practice and risk management

Lynch syndrome is the most common cause of hereditary colon cancer, and accounts for as much as 3% of all colon and endometrial cancers. The identification and management of individuals with Lynch syndrome have evolved over the past 20 years, yet the syndrome remains vastly underdiagnosed. It is important for clinicians to recognize individuals and families who are at risk in order to be able to manage them appropriately and reduce their morbidity and mortality from this condition. This review will touch on the history of Lynch syndrome, the current knowledge of genotype–phenotype correlations, the cancers associated with Lynch syndrome, and management of individuals who are gene carriers.

The prognostic value of family history among patients with urinary bladder cancer

A history of urinary bladder cancer (UBC) in first-degree relatives increases UBC risk by twofold. The influence of positive family history on UBC prognosis is unknown. Here, we investigated association of first-degree UBC family history with clinicopathological characteristics and prognosis of UBC patients. Detailed clinical data of 1,465 non-muscle-invasive bladder cancer (NMIBC) and 250 muscle-invasive or metastatic bladder cancer (MIBC) patients, diagnosed from 1995 to 2010, were collected through medical file review. Competing risk analyses were used to compare recurrence-free survival (RFS) and progression-free survival (PFS) of NMIBC patients according to self-reported UBC family history. Overall survival in MIBC patients was estimated using Kaplan-Meier analysis. The added value of family history in prediction of NMIBC prognosis was quantified with Harrell's concordance-index. Hundred (6.8%) NMIBC and 14 (5.6%) MIBC patients reported UBC in first-degree relatives. Positive family history was statistically significantly associated with smaller tumor size and non-significantly with more favorable distribution of other tumor characteristics. In univariable analyses, positive family history correlated with longer RFS (p = 0.11) and PFS (p = 0.04). Hazard ratios for positive vs. negative family history after adjustment for clinicopathological characteristics were 0.75 (95% CI = 0.53–1.07) and 0.45 (95% CI = 0.18–1.12) for RFS and PFS, respectively. Five familial and 48 sporadic MIBC patients (Kaplan-Meier 10-year risk: 41% and 25%) died within 10 years. Family history did not improve the c-index of prediction models. This study shows that a first-degree family history of UBC is not clearly associated with NMIBC prognosis. Family history does not aid in prediction of NMIBC recurrence or progression.

Hereditary colorectal cancer syndromes and genetic testing

Colorectal cancer (CRC) is a leading cause of cancer and cancer deaths in the Western world. Approximately 5-10% of CRC are hereditary, due to a defined genetic cause. Individuals and families affected with a hereditary CRC syndrome exhibit benign and malignant extra-intestinal tumors, require aggressive cancer screening and benefit from management by a multi-disciplinary team of professionals. The clinical manifestations, genetic causes and current management of patients with hereditary colon cancer syndrome is provided.

Patient experiences with gene panels based on exome sequencing in clinical diagnostics: high acceptance and low distress

The Radboud University Medical Center was among the first to implement two-step exome sequencing in clinical genetic diagnostics. This study is the first to evaluate patient experiences with gene panels based on exome sequencing, using quantified psychological variables: acceptance, psychological distress, expectations of heredity and unsolicited findings. Between August 2011 and July 2012, 177 patients diagnosed with early-onset colorectal/kidney cancer, deafness, blindness or movement disorder consented to diagnostic exome sequencing offered by clinical geneticists. Baseline questionnaires were sent to 141 adults, returned by 111 with median age of 49 [22-79] years and positive family history in 81%. Follow-up included 91 responders at median 4 [2-22] weeks after results from known gene panels per diagnosis group; exome-wide analysis is ongoing. Confirmed or possibly pathogenic mutations were found in 31% with one unsolicited finding (oncogenetic panel). Most patients (92%) were satisfied. There were no significant changes in heredity-specific distress (18% at baseline, 17% at follow-up) and expectations of heredity. Fewer patients expected unsolicited findings at follow-up (29% vs 18%, p = 0.01). Satisfaction and distress were equal in those with vs without mutations. In conclusion, most adults accepted and were satisfied with gene panels based on diagnostic exome sequencing, few reporting distress.

Familial urothelial cell carcinoma of the bladder with autosomal dominant inheritance and late onset phenotype

Objective

Familial Urothelial cell bladder cancer is rare. We report two families with urothelial cell carcinoma (UCC) of bladder with family history in other relatives, displaying probable autosomal dominant inheritance and a late onset pure UCC phenotype, and document the phenotype in each family.

Methods

Descriptive familial study on two pedigrees over three generations.

Results

Two families with UCC bladder were identified, and the phenotype documented, each family having three cases of late onset UCC.

Conclusion

Some cases of UCC are hereditary and may display autosomal dominant inheritance with late onset of the cancer. Clinicians should be aware of the existence of a familial late onset UCC phenotype when managing cases of UCC.

Lynch syndrome 101 (years, that is)

Lynch syndrome was described over a century ago but information on the medical consequences and optimal management of this disorder continue to amass and evolve. This brief overview highlights the gene-specific and site-specific cancer penetrance and management options for those with Lynch syndrome.

Gender-Specific Aspects of Lynch Syndrome and Familial Adenomatous Polyposis

BACKGROUND

The most frequent hereditary colorectal cancer (CRC) syndromes are Lynch syndrome and familial adenomatous polyposis (FAP), accounting for approximately 5% of the CRC burden. Both are characterized by an autosomal dominant mode of transmission and require an individualized approach of intensified screening and prophylactic surgery.

METHODS

In this review, we provide an overview of the literature regarding gene- and gender-specific aspects of Lynch syndrome and FAP. Based upon available data, a personalized approach when treating patients and families with these predisposition syndromes is increasingly warranted.

RESULTS

In Lynch syndrome patients, men have a significantly higher lifetime risk and earlier age of manifestation for CRC - especially in MSH6 mutation carriers. Moreover, incidence of gastric, bladder, and urothelial cancers is much higher in males. Females with an MSH6 mutation have to be aware of a very high risk especially for endometrial, but also for ovarian cancer. In FAP families, females are more prone to papillary thyroid cancers and also to desmoid tumors.

CONCLUSION

It is timely to suggest gene- and gender-based adapted screening and surgical recommendations for Lynch syndrome patients. In FAP patients, females should follow intensified screening recommendations for early detection of precursors or papillary cancer of the thyroid. Moreover, desmoid patients should primarily not be subjected to surgical resection but rather to a gender-specific conservative medical treatment.

Lynch syndrome-associated neoplasms: a discussion on histopathology and immunohistochemistry

It was a century ago that Warthin, a pathologist, first described the clinical condition now known as Lynch syndrome. One hundred years later, our understanding of this syndrome has advanced significantly. Much of the progress took place over the last 25 years and was marked by a series of interacting developments from the disciplines of clinical oncology, pathology, and molecular genetics, with each development serving to guide or enhance the next. The advancement of our understanding about the pathology of Lynch syndrome associated tumors exemplifies such intimate interplay among disciplines. Today, accumulative knowledge has enabled surgical pathologists to detect tumors that are likely to be associated with Lynch syndrome, and the pathologist is playing an increasingly more important role in the care of these patients. The pathologist's ability is afforded primarily by information gained from tumor histopathology and by DNA mismatch repair protein immunohistochemistry. It is therefore pertinent both for the pathologists to accurately ascertain this morphologic information, and for all that are involved in the care of these patients to thoroughly understand the implications of such information. This article provides an overview of the development of histopathology and immunohistochemistry in Lynch syndrome-associated tumors, particularly in colorectal and endometrial cancers, and outlines the issues and current status of these specific pathologic aspects in not only the major tumors but also those less commonly seen or only newly reported in Lynch syndrome patients.

Cancer risk in Lynch Syndrome

Lynch Syndrome, or hereditary non-polyposis colorectal cancer (HNPCC) is an autosomal dominant cancer predisposition syndrome caused by inactivating mutations in DNA mismatch repair genes. It accounts for 2-4 % of all incident colorectal cancers. Mutation carriers are at risk of early onset colorectal cancer, endometrial cancer, and a spectrum of other tumours. Accurate estimation of cancer risk for mutation carriers is essential for counselling, and establishing appropriate screening guidelines. This study reviews the current data on cancer risk, and emerging risk reduction strategies.

A clinical scoring system to identify patients with sebaceous neoplasms at risk for the Muir-Torre variant of Lynch syndrome

PURPOSE

The Muir-Torre syndrome variant of Lynch syndrome is characterized by the presence of sebaceous neoplasms (adenoma, epithelioma/sebaceoma, carcinoma) and Lynch syndrome-associated cancers (colon, endometrial, and others). Several clinical scoring systems have been developed to identify patients with colon cancer at high risk of Lynch syndrome. However, no such system has been described for patients presenting with sebaceous neoplasms.

METHODS

Based on logistic regression analysis, a scoring system was developed for patients with sebaceous neoplasm to identify those with the highest likelihood of having Muir-Torre syndrome. The final version of the scoring system included variables such as age at presentation of initial sebaceous neoplasm, total number of sebaceous neoplasms, personal history of a Lynch-related cancer, and family history of Lynch-related cancers.

RESULTS

Patients with a score of 3 or more were more likely to have Muir-Torre syndrome (28 of 29 patients), those with a score of 2 had intermediate likelihood (12 of 20 patients), and no patient with a score of 0 or 1 was diagnosed with Muir-Torre syndrome.

CONCLUSION

The Mayo Muir-Torre syndrome risk scoring system appears to identify whether patients who present with sebaceous neoplasms are in need of further Lynch syndrome evaluation using easily ascertained clinical information. Abnormal mismatch repair gene immunohistochemistry of a sebaceous neoplasm is a poor predictor in regard to diagnosing Lynch syndrome.

Easy-to-use online referral test detects most patients with a high familial risk of colorectal cancer

AIM

Currently only 12-30% of individuals with a high risk of Lynch syndrome, the most common hereditary colorectal cancer (CRC) syndrome, are referred for genetic counselling. We assessed the sensitivity, usability and user experiences of a new online referral test aimed at improving referral of high-risk individuals for genetic counselling.

METHOD

Sensitivity was assessed by entering pedigree data from high-risk individuals (i.e. Lynch syndrome mutation carriers) into the referral test to determine whether genetic counselling was recommended. For usability, we assessed nonmedical staff members' ability to determine referral, according to guidelines, in seven fictive clinical cases using the referral test after minimal training. Real-life users answered questions about their experience with the referral test.

RESULT

Sensitivity of the referral test was 91% for mutation carriers with CRC (n = 164) and 73% for all affected and nonaffected mutation carriers (n = 420). Nonmedical staff members (n = 20) determined referral according to guidelines in 84% of cases using the referral test. Ten per cent (256/2470) of real-life users provided feedback about experiences; of those, 71% reported that the referral test increased reassurance, certainty about their familial risk and/or certainty about referral.

CONCLUSION

The referral test has a high sensitivity in detecting individuals with a high risk of Lynch syndrome and is suitable for use in clinical practice. Widespread use of the referral test should improve cancer prevention in high-risk patients and their relatives.

Excess of extracolonic non-endometrial multiple primary cancers in MSH2 germline mutation carriers over MLH1

BACKGROUND

The lynch syndrome (LS) tumor spectrum involves colorectal cancer (CRC), endometrial cancer (EC), and less frequently various extracolonic non-endometrial cancers (non-EC). The organ-specific survival rates of these patients are well defined, however, the collective survival of all-cancers combined (CRC + EC + non-EC) are unclear.

METHODS

Fifty-two MSH2 patients and 68 MLH1 patients were followed for a median of 6.3 years after diagnosis of first cancer, regardless of type. The proportions of CRC only, EC, non-EC, and multiple primary cancers were compared between the two genotypes. Kaplan-Meier curves were developed for survival comparisons.

RESULTS

MSH2 patients present less frequently with only CRC (37% MSH2, 62% MLH1, P = 0.0096), manifest more multiple primary cancers (38% MSH2, 18% MLH1, P = 0.013), develop more extracolonic cancers (62% MSH2, 38% MLH1, P = 0.003), non-EC only cancers (46% MSH2, 24% MLH1, P = 0.028) and carry a greater risk for urinary tract cancer (UTC) (13.4% MSH2, 1.5% MLH1, P = 0.024). There was no difference in 10-year survival between the two groups (P = 0.4).

CONCLUSION

The additional propensity for UTC in MSH2 carriers argues in favor of UTC screening in MSH2 individuals. Other types of cancer screening should be tailored to the expression history of the specific LS mutation.

Genetic testing strategies in newly diagnosed endometrial cancer patients aimed at reducing morbidity or mortality from lynch syndrome in the index case or her relatives

Endometrial cancer is the first malignancy in 50% of women with Lynch syndrome, an autosomal dominant cancer-prone syndrome caused by germline mutations in genes encoding components of the DNA mismatch repair (MMR) pathway. These women (2-4% of all those with endometrial cancer) are at risk of metachronous colorectal cancer and other Lynch syndrome-associated cancers, and their first-degree relatives are at 50% risk of Lynch syndrome. Testing all women newly diagnosed with endometrial cancer for Lynch syndrome may have clinical utility for the index case and her relatives by alerting them to the benefits of surveillance and preventive options, primarily for colorectal cancer. The strategy involves offering germline DNA mutation testing to those whose tumour shows loss-of-function of MMR protein(s) when analysed for microsatellite instability (MSI) and/or by immunohistochemisty (IHC). In endometrial tumours from unselected patients, MSI and IHC have a sensitivity of 80-100% and specificity of 60-80% for detecting a mutation in an MMR gene, though the number of suitable studies for determining clinical validity is small. The clinical validity of strategies to exclude those with false-positive tumour test results due to somatic hypermethylation of the MLH1 gene promoter has not been determined. Options include direct methylation testing, and excluding those over the age of 60 who have no concerning family history or clinical features. The clinical utility of Lynch syndrome testing for the index case depends on her age and the MMR gene mutated: the net benefit is lower for those diagnosed at older ages and with less-penetrant MSH6 mutations. To date, women with these features are the majority of those diagnosed through screening unselected endometrial cancer patients but the number of studies is small. Similarly, clinical utility to relatives of the index case is higher if the family's mutation is in MLH1 or MSH2 than for MSH6 or PMS2. Gaps in current evidence include a need for large, prospective studies on unselected endometrial cancer patients, and for health-economic analysis based on appropriate assumptions.

Revised guidelines for the clinical management of Lynch syndrome (HNPCC): recommendations by a group of European experts

Lynch syndrome (LS) is characterised by the development of colorectal cancer, endometrial cancer and various other cancers, and is caused by a mutation in one of the mismatch repair genes: MLH1, MSH2, MSH6 or PMS2. In 2007, a group of European experts (the Mallorca group) published guidelines for the clinical management of LS. Since then substantial new information has become available necessitating an update of the guidelines. In 2011 and 2012 workshops were organised in Palma de Mallorca. A total of 35 specialists from 13 countries participated in the meetings. The first step was to formulate important clinical questions. Then a systematic literature search was performed using the Pubmed database and manual searches of relevant articles. During the workshops the outcome of the literature search was discussed in detail. The guidelines described in this paper may be helpful for the appropriate management of families with LS. Prospective controlled studies should be undertaken to improve further the care of these families.

Elevated risk of prostate cancer among men with Lynch syndrome

PURPOSE

Prostate cancer has been described as a component tumor of Lynch syndrome (LS), with tumors obtained from mutation carriers demonstrating the DNA mismatch repair deficiency phenotype. Previous studies quantifying prostate cancer risk in LS have provided conflicting results.

METHODS

We examined cancer histories of probands and their first- through fourth-degree relatives for 198 independent mutation-positive LS families enrolled in two US familial cancer registries. Modified segregation analysis was used to calculate age-specific cumulative risk or penetrance estimates, with accompanying Wald-type CIs. Cumulative lifetime risks and hazard ratio (HR) estimates for prostate cancer were calculated and compared with those of the general population.

RESULTS

Ninety-seven cases of prostate cancer were observed in 4,127 men. Median age at prostate cancer diagnosis was 65 years (range, 38 to 89 years), with 11.53% of affected individuals diagnosed before age 50 years. The cumulative risk of prostate cancer at ages 60 and 80 years was 6.30% (95% CI, 2.47 to 9.96) and 30.0% (95% CI, 16.54 to 41.30), as compared with the population risk of 2.59% and 17.84%, respectively. The overall prostate cancer HR among carriers was 1.99 (95% CI, 1.31 to 3.03).

CONCLUSION

The cumulative lifetime risk of prostate cancer in individuals with LS is two-fold higher than in the general population and is slightly higher in carriers diagnosed before age 60 years (HR, 2.48; 95% CI, 1.34 to 4.59). These estimates are clinically valuable to quantify risk for both patients and providers.

Uroepithelial and kidney carcinoma in Lynch syndrome

Increased risk for urological tumors has been observed in mutation carriers with Lynch syndrome (LS). In this study, we evaluated the clinical features of uroepithelial (bladder and ureter) and kidney cancers in 974 Finnish mutation carriers. Altogether 30 patients had a total of 34 urological tumors: 12 ureter, 12 bladder, and 10 kidney cancers. Urological tumor was the only tumor in 9 (30 %) patients, and metachronous other tumor occurred in 21 (70 %). The occurrence of uroepithelial cancers was significantly higher in MSH2 mutation carriers (6 %; 95 % CI, 2.7-11.0) than in MLH1 carriers (2 %; 95 % CI, 1.1-3.2) and MSH6 mutation carriers (0 %) (p = 0.014). The mean ages of patients at the time of diagnosis were: bladder cancer, 57 years; ureter cancer, 58 years; and kidney cancer, 64 years. Overall 5-year survival rates were 70 % (95 % CI, 0.32-0.89) in bladder cancer, 81 % (95 % CI, 0.45-0.95) in ureter cancer, and 75 % (95 % CI, 0.31-0.93) in kidney cancer. Cancer-specific 5-year survival rates were 70 % (95 % CI, 0.32-0.89) in bladder cancer, 91 % (95 % CI, 0.51-0.98) in ureter cancer, and 100 % in kidney cancer. In conclusion, early age of onset was observed in patients with uroepithelial tumors, but not in patients with kidney cancer. The frequency of uroepithelial tumors was significantly higher in MSH2 mutation carriers than in MLH1 carriers. Further studies with larger numbers of patients, however, are needed to evaluate the potential benefit of surveillance of urological tumors in LS.

The spectrum of urological malignancy in Lynch syndrome

Urological tumours are the third most frequent malignancy in Lynch syndrome after colonic and endometrial cancer. Upper urinary tract tumours are well recognised in Lynch syndrome, but the association with prostate and bladder cancer is controversial. We determined the incidence and cumulative and relative risks of prostate and bladder cancer in a cohort of Lynch syndrome families. Male Lynch syndrome mutation carriers and their genetically untested male first degree relatives (FDR) were identified from the Manchester Regional Lynch syndrome database (n = 821). Time to the development of urological cancer was identified for each urological site (renal pelvis, ureter, bladder and prostate). Cumulative and relative risks were calculated, with results classified by mutation carrier status and specific causative genetic mutations. Eight prostate cancers were identified, only one occurring before the age of 60. Analysis of person-years at risk of prostate cancer by Lynch syndrome mutation carrier status suggests a correlation between MSH2 mutation carriers and a tenfold increased risk of prostate cancer (RR 10.41; 95 % CI 2.80, 26.65). No such association was found with bladder cancer (RR 1.88; 95 % CI 0.21, 6.79). The association of upper urinary tract tumours with MSH2 and MLH1 mutations was confirmed. We have carried out the largest study of male Lynch syndrome mutation carriers to establish the risks of urological malignancy. A tenfold increased risk of prostate cancer is supported in MSH2 with mutation carriers having roughly double the risk of prostate cancer to FDRs. A trial of PSA testing in MSH2 carriers from 40 to 50 years may be justifiable.

Risks of less common cancers in proven mutation carriers with lynch syndrome

PURPOSE

Patients with Lynch syndrome are at high risk for colon and endometrial cancer, but also at an elevated risk for other less common cancers. The purpose of this retrospective cohort study was to provide risk estimates for these less common cancers in proven carriers of pathogenic mutations in the mismatch repair (MMR) genes MLH1, MSH2, and MSH6.

PATIENTS AND METHODS

Data were pooled from the German and Dutch national Lynch syndrome registries. Seven different cancer types were analyzed: stomach, small bowel, urinary bladder, other urothelial, breast, ovarian, and prostate cancer. Age-, sex- and MMR gene-specific cumulative risks (CRs) were calculated using the Kaplan-Meier method. Sex-specific incidence rates were compared with general population incidence rates by calculating standardized incidence ratios (SIRs). Multivariate Cox regression analysis was used to estimate the impact of sex and mutated gene on cancer risk.

RESULTS

The cohort comprised 2,118 MMR gene mutation carriers (MLH1, n = 806; MSH2, n = 1,004; MSH6, n = 308). All cancers were significantly more frequent than in the general population. The highest risks were found for male small bowel cancer (SIR, 251; 95% CI, 177 to 346; CR at 70 years, 12.0; 95% CI, 5.7 to 18.2). Breast cancer showed an SIR of 1.9 (95% CI, 1.4 to 2.4) and a CR of 14.4 (95% CI, 9.5 to 19.3). MSH2 mutation carriers had a considerably higher risk of developing urothelial cancer than MLH1 or MSH6 carriers.

CONCLUSION

The sex- and gene-specific differences of less common cancer risks should be taken into account in cancer surveillance and prevention programs for patients with Lynch syndrome.

Risks of primary extracolonic cancers following colorectal cancer in lynch syndrome

BACKGROUND

Lynch syndrome is a highly penetrant cancer predisposition syndrome caused by germline mutations in DNA mismatch repair (MMR) genes. We estimated the risks of primary cancers other than colorectal cancer following a diagnosis of colorectal cancer in mutation carriers.

METHODS

We obtained data from the Colon Cancer Family Registry for 764 carriers of an MMR gene mutation (316 MLH1, 357 MSH2, 49 MSH6, and 42 PMS2), who had a previous diagnosis of colorectal cancer. The Kaplan-Meier method was used to estimate their cumulative risk of cancers 10 and 20 years after colorectal cancer. We estimated the age-, sex-, country- and calendar period-specific standardized incidence ratios (SIRs) of cancers following colorectal cancer, compared with the general population.

RESULTS

Following colorectal cancer, carriers of MMR gene mutations had the following 10-year risk of cancers in other organs: kidney, renal pelvis, ureter, and bladder (2%, 95% confidence interval [CI] = 1% to 3%); small intestine, stomach, and hepatobiliary tract (1%, 95% CI = 0.2% to 2%); prostate (3%, 95% CI = 1% to 5%); endometrium (12%, 95% CI = 8% to 17%); breast (2%, 95% CI = 1% to 4%); and ovary (1%, 95% CI = 0% to 2%). They were at elevated risk compared with the general population: cancers of the kidney, renal pelvis, and ureter (SIR = 12.54, 95% CI = 7.97 to 17.94), urinary bladder (SIR = 7.22, 95% CI = 4.08 to 10.99), small intestine (SIR = 72.68, 95% CI = 39.95 to 111.29), stomach (SIR = 5.65, 95% CI = 2.32 to 9.69), and hepatobiliary tract (SIR = 5.94, 95% CI = 1.81 to 10.94) for both sexes; cancer of the prostate (SIR = 2.05, 95% CI = 1.23 to 3.01), endometrium (SIR = 40.23, 95% CI = 27.91 to 56.06), breast (SIR = 1.76, 95% CI = 1.07 to 2.59), and ovary (SIR = 4.19, 95% CI = 1.28 to 7.97).

CONCLUSION

Carriers of MMR gene mutations who have already had a colorectal cancer are at increased risk of a greater range of cancers than the recognized spectrum of Lynch syndrome cancers, including breast and prostate cancers.

Patients with Lynch syndrome mismatch repair gene mutations are at higher risk for not only upper tract urothelial cancer but also bladder cancer

BACKGROUND

Lynch syndrome (LS), or hereditary nonpolyposis colorectal cancer, is caused by mutations in mismatch repair (MMR) genes. An increased risk for upper tract urothelial carcinoma (UTUC) has been described in this population; however, data regarding the risk for bladder cancer (BCa) are sparse.

OBJECTIVE

To assess the risk of BCa in MMR mutation carriers and suggest screening and management recommendations.

DESIGN, SETTING, AND PARTICIPANTS

Cancer data from 1980 to 2007 were obtained from the Familial Gastrointestinal Cancer Registry in Toronto for 321 persons with known MMR mutations: mutL homolog 1, colon cancer, nonpolyposis type 2 (E. coli) (MLH1); mutS homolog 2, colon cancer, nonpolyposis type 1 (E. coli) (MSH2); mutS homolog 6 (E. coli) (MSH6); and PMS2 postmeiotic segregation increased 2 (S. cerevisiae) (PMS2).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Standardized incidence ratios from the Ontario Cancer Registry, using the Surveillance Epidemiology and End Results public database, were used to compare cancer risk in patients with MMR mutations with the Canadian population. Microsatellite instability analysis and immunohistochemistry (IHC) of the MMR proteins were also performed and the results compared with matched sporadic bladder tumors.

RESULTS AND LIMITATIONS

Eleven of 177 patients with MSH2 mutations (6.21%, p<0.001 compared with the Canadian population) were found to have BCa, compared with 3 of 129 patients with MLH1 mutations (2.32%, p>0.05). Of these 11 tumors, 81.8% lacked expression of MSH2 on IHC, compared with the matched sporadic cases, which all displayed normal expression of MSH2 and MLH1. The incidence of UTUC among MSH2 carriers was 3.95% (p<0.001), and all tumors were found to be deficient in MSH2 expression on IHC. Mutations in the intron 5 splice site and exon 7 of the MSH2 gene increased the risk of urothelial cancer. Limitations include possible inflated risk estimates due to ascertainment bias.

CONCLUSIONS

LS patients with MSH2 mutations are at an increased risk for not only UTUC but also BCa and could be offered appropriate screening.

Clinicopathological features and management of cancers in lynch syndrome

Lynch syndrome (LS) is characterized by an autosomal dominant inheritance of the early onset of colorectal cancer (CRC) and endometrial cancer, as well as increased risk for several other cancers including gastric, urinary tract, ovarian, small bowel, biliary tract, and brain tumors. The syndrome is due to a mutation in one of the four DNA mismatch repair (MMR) genes MLH1, MSH2, MSH6, or PMS2. The majority of LS patients and families can now be identified, and the underlying mutation detected using genetic diagnostics. Regular surveillance for CRC and endometrial cancer has proved beneficial for mutation carriers. However, screening for other tumors is also recommended even though experiences in the screening of these tumors is limited. Prophylactic colectomy, prophylactic hysterectomy, and bilateral salpingo-oophorectomy may be reasonable options for selected patients with LS. This paper describes the features and management of LS.

Haematuria in association with Lynch syndrome

A 40-year-old Caucasian male presented to the Emergency Department complaining of intermittent painless frank haematuria. Past medical history was significant for Hereditary Non-Polyposis Colon Cancer (HNPCC) and a prophylactic total colectomy. Computed tomography urogram showed thickening in the posterior wall of the bladder. Cystoscopy showed a small bladder mass. Histology showed a papillary urothelial neoplasm of low malignant potential. HNPCC, also known as Lynch Syndrome, is an autosomal dominant disorder responsible for 3-5% of colorectal cancers. There are certain cancers known to be associated with HNPCC; colorectal cancer, endometrial, ovarian, stomach, pancreas, biliary tract, small bowel, brain, renal pelvic and ureteric tumours, sebaceous gland adenomas and keratocanthomas. An association with bladder tumours is not well established.

Adrenocortical carcinoma, an unusual extracolonic tumor associated with Lynch II syndrome

Lynch syndrome (LS) is an autosomal dominant condition that predisposes to colorectal cancer and specific other tumors. Extracolonic tumors occur mainly in the endometrium, stomach, ovary, small intestine and urinary tract. The presence of rare tumors in patients belonging to families who have Lynch syndrome is always interesting, because the question arises whether these tumors should be considered as a coincidence or are related with the syndrome. In this last case, they are also the result of the defect in the mismatch repair system, opening the possibility of extending the tumor spectrum associated with the syndrome. Here we describe a patient from a Lynch syndrome family with a germline mutation c.2063T>G (p.M688R) in the MSH2 gene, who developed an adrenal cortical carcinoma, a tumor not usually associated with LS. We analyzed the adrenocortical tumour for microsatellite instability (MSI), LOH and the presence of the germline c.2063T>G (M688R) mutation. The adrenal cortical carcinoma showed the MSH2 mutation, loss of heterozygosity of the normal allele in the MSH2 gene and loss of immunohistochemical expression for MSH2 protein, but no microsatellite instability. Additionally, the adrenal cortical carcinoma did not harbour a TP53 mutation. The molecular study indicates that this adrenal cortical cancer is probably due to the mismatch repair defect.

Personalized therapy for urothelial cancer: review of the clinical evidence

Despite a detailed understanding of the molecular aberrations driving the development of urothelial cancers, this knowledge has not translated into advances for the treatment of this disease. Urothelial cancers are chemosensitive, and platinum-based combination chemotherapy remains the standard of care for advanced disease, as well as neoadjuvant and adjuvant therapy for locally advanced disease. However, nearly half of patients who undergo resection of locally advanced urothelial cancer will relapse and eventually develop platinum-resistant disease. Clinical trials of targeted agents against angiogenesis and growth factors, as well as novel chemotheraputics, have generally been unsuccessful in urothelial cancers. Improvements in the theraputic arsenal for urothelial cancer depend upon identification of new targets and strategies to overcome platinum resistance.

[Differential diagnostics of hereditary colorectal cancer syndromes. The role of pathology]

One third of colorectal carcinomas (CRC) show familial clustering of which about 5% have a monogenetic trait. Distinction between disease with and without polyposis, tumor histology and tumor spectrum in a given patient are all of diagnostic relevance. Familial adenomatous polyposis (FAP) underlies approximately 1% of CRC characterized by rapidly forming (>100) adenomas. In contrast to these about 2%-3% of CRC have a hereditary background without polyposis (HNPCC). This is the only hereditary tumour syndrome to date for which a tissue-based molecular screening test is available. Accordingly, expression analysis of mismatch repair genes (MSH2, MSH6 and MLH1, PMS2) is performed first. In the case of an equivocal result with no complete loss of expression testing of microsatellite instability (MSI) is added. In contrast to the other diseases MYH-associated polyposis (MAP) follows a recessive trait with polyp numbers usually between 15-30 adenomas and should be distinguished from attenuated forms of FAP with <100 polyps in the differential diagnosis. In the case of suspected familial cancer syndrome genetic counseling is warranted in order to decide ultimately whether there is an indication for genetic testing (evidence of a germ-line mutation).

Risk of colorectal and endometrial cancers in EPCAM deletion-positive Lynch syndrome: a cohort study

BACKGROUND

Lynch syndrome is caused by germline mutations in MSH2, MLH1, MSH6, and PMS2 mismatch-repair genes and leads to a high risk of colorectal and endometrial cancer. We previously showed that constitutional 3' end deletions of EPCAM can cause Lynch syndrome through epigenetic silencing of MSH2 in EPCAM-expressing tissues, resulting in tissue-specific MSH2 deficiency. We aim to establish the risk of cancer associated with such EPCAM deletions.

METHODS

We obtained clinical data for 194 carriers of a 3' end EPCAM deletion from 41 families known to us at the Radboud University Nijmegen Medical Centre, Nijmegen, Netherlands and compared cancer risk with data from a previously described cohort of 473 carriers from 91 families with mutations in MLH1, MSH2, MSH6, or a combined EPCAM-MSH2 deletion.

FINDINGS

93 of the 194 EPCAM deletion carriers were diagnosed with colorectal cancer; three of the 92 women with EPCAM deletions were diagnosed with endometrial cancer. Carriers of an EPCAM deletion had a 75% (95% CI 65-85) cumulative risk of colorectal cancer before the age of 70 years (mean age at diagnosis 43 years [SD 12]), which did not differ significantly from that of carriers of combined EPCAM-MSH2 deletion (69% [95% CI 47-91], p=0·8609) or mutations in MSH2 (77% [64-90], p=0·5892) or MLH1 (79% [68-90], p=0·5492), but was higher than noted for carriers of MSH6 mutation (50% [38-62], p<0·0001). By contrast, women with EPCAM deletions had a 12% [0-27] cumulative risk of endometrial cancer, which was lower than was that noted for carriers of a combined EPCAM-MSH2 deletion (55% [20-90], p<0·0001) or of a mutation in MSH2 (51% [33-69], p=0·0006) or MSH6 (34% [20-48], p=0·0309), but did not differ significantly from that noted for MLH1 (33% [15-51], p=0·1193) mutation carriers. This risk seems to be restricted to deletions that extend close to the MSH2 gene promoter. Of 194 carriers of an EPCAM deletion, three had duodenal cancer and four had pancreatic cancer.

INTERPRETATION

EPCAM deletion carriers have a high risk of colorectal cancer; only those with deletions extending close to the MSH2 promoter have an increased risk of endometrial cancer. These results underscore the effect of mosaic MSH2 deficiency, leading to variable cancer risks, and could form the basis of an optimised protocol for the recognition and targeted prevention of cancer in EPCAM deletion carriers.

The revised Bethesda guidelines: extent of utilization in a university hospital medical center with a cancer genetics program

BACKGROUND

In 1996, the National Cancer Institute hosted an international workshop to develop criteria to identify patients with colorectal cancer who should be offered microsatellite instability (MSI) testing due to an increased risk for Hereditary Nonpolyposis Colorectal Cancer (HNPCC). These criteria were further modified in 2004 and became known as the revised Bethesda Guidelines. Our study aimed to retrospectively evaluate the percentage of patients diagnosed with HNPCC tumors in 2004 who met revised Bethesda criteria for MSI testing, who were referred for genetic counseling within our institution.

METHODS

All HNPCC tumors diagnosed in 2004 were identified by accessing CoPath, an internal database. Both the Tumor Registry and patients' electronic medical records were accessed to collect all relevant family history information. The list of patients who met at least one of the revised Bethesda criteria, who were candidates for MSI testing, was then cross-referenced with the database of patients referred for genetic counseling within our institution.

RESULTS

A total of 380 HNPCC-associated tumors were diagnosed at our institution during 2004 of which 41 (10.7%) met at least one of the revised Bethesda criteria. Eight (19.5%) of these patients were referred for cancer genetic counseling of which 2 (25%) were seen by a genetics professional. Ultimately, only 4.9% of patients eligible for MSI testing in 2004 were seen for genetic counseling.

CONCLUSION

This retrospective study identified a number of barriers, both internal and external, which hindered the identification of individuals with HNPCC, thus limiting the ability to appropriately manage these high risk families.

Genetic counseling considerations in the evaluation of families for Lynch syndrome--a review

Lynch syndrome is the most common hereditary colorectal cancer syndrome and the most common cause of hereditary endometrial cancer. Identifying and evaluating families for Lynch syndrome is increasing in complexity due to the recognition that: family history-based clinical criteria lack sensitivity and specificity; genetic testing for Lynch syndrome continues to evolve as understanding of the molecular mechanisms underlying it evolves; and the Lynch syndrome phenotype encompasses multiple organ systems and demonstrates overlap with other hereditary cancer syndromes. This document is a summary of considerations when evaluating individuals and families for Lynch syndrome, including information on cancer risks, diagnostic criteria, tumor and genetic testing strategies, and the management of individuals with this condition.