Amsterdam II Criteria Research Articles

Somatic BRAF V600E Mutation in Familial Colorectal Cancer Type X: A New Study in Central Iran

Background: BRAF-V600E is a known prognostic/predictive marker in colorectal cancer (CRC), detected in 4 - 12% of all patients with this cancer. Familial-CRC-type-X (FCCX) is a subtype of mismatch-repair (MMR) proficient CRC with an unknown genetic cause. Objectives: Given the lack of enough information on the molecular aspects of FCCX among Iranians, this study was conducted to evaluate the BRAF-V600E hot-spot mutation in tumor DNA in FCCX probands in Central Iran. Methods: This was a cross-sectional study in which 48 FCCX probands were recruited according to Amsterdam-II criteria, and MMR proficiency was confirmed by MSI testing and IHC-MMRs. Tumors’ DNA samples were assessed for the BRAF-V600E mutation by Sanger-sequencing. Results: None of the 48 assessed FCCX probands presented the BRAF-V600E mutation. Conclusions: It can be suggested that FCCX tumors have a good prognosis compared to other CRCs.

Different surgical outcome and follow-up status between dMMR and pMMR colorectal cancer patients who fulfilled with Amsterdam-II criteria

BackgroundAlthough hereditary non-polyposis colorectal cancer (HNPCC) could be subtyped into proficient or deficient mismatch repair gene expression (pMMR or dMMR), distinct clinical features between these two subgroups patients were rarely reported.MethodsWe retrospectively analyzed 175 hereditary non-polyposis colorectal cancer (HNPCC) patients between January 1995 and December 2012. Cox proportional hazards model was used to compare the differences between two subgroups.ResultsSignificant differences of disease free survival (DFS) and overall survival (OS) exist between dMMR and pMMR. In addition to other factors including younger mean age of diagnosis for dMMR patients (48.6 years vs. 54.3 years), operation type (more extended colectomy for dMMR 35.8% vs. 14.5%), tumor location (right colon predominance for dMMR 61.7% vs. 27.3% and more rectum cases for pMMR 41.8% vs. 11.7%), tumor differentiation (more poor differentiation for dMMR 23.3% vs. 9.0%), N staging (more N0 cases for dMMR 70.8% vs. 50.9%), more frequently presence of extra-colonic tumors for dMMR (16.7% vs.1.8%), and lower recurrence rates (9.1% vs.35.3%). Significantly different cumulative incidences of developing metachronous colorectal cancer were observed with 6.18 for pMMR patients and 20.57 person-years for dMMR patients (p < 0.001).ConclusionsDistinct clinicopathological features significantly exist between dMMR and pMMR subtypes patient, MMR status should be consider to tailor operation types and follow up surveillance between these two subgroups patients who all fulfilled with Amsterdam-II criteria.

Cancer risks in Lynch syndrome, Lynch-like syndrome, and familial colorectal cancer type X: a prospective cohort study

BackgroundIndividuals with pathogenic germline variants in DNA mismatch repair (MMR) genes are at increased risk of developing colorectal, endometrial and other cancers (Lynch syndrome, LS). While previous studies have extensively described cancer risks in LS, cancer risks in individuals from families without detectable MMR gene defects despite MMR deficiency (Lynch-like syndrome, LLS), and in individuals from families fulfilling the Amsterdam-II criteria without any signs of MMR deficiency (familial colorectal cancer type X, FCCX) are less well studied. The aim of this prospective study was to characterise the risk for different cancer types in LS, LLS, and FCCX, and to compare these with the cancer risks in the general population.MethodsData was taken from the registry of the German Consortium for Familial Intestinal Cancer, where individuals were followed up prospectively within the framework of an intensified surveillance programme at recommended annual examination intervals. A total of 1120 LS, 594 LLS, and 116 FCCX individuals were analysed. From this total sample, eight different cohorts were defined, in which age-dependent cumulative risks and standardised incidence ratios were calculated regarding the first incident occurrence of any, colorectal, stomach, small bowel, urothelial, female breast, ovarian, and endometrial cancer, separately for LS, LLS, and FCCX.ResultsThe number of individuals at risk for first incident cancer ranged from 322 to 1102 in LS, 120 to 586 in LLS, and 40 to 116 in FCCX, depending on the cancer type of interest. For most cancer types, higher risks were observed in LS compared to LLS, FCCX, and the general population. Risks for any, colorectal, stomach, urothelial, and endometrial cancer were significantly higher in LLS compared to the general population. No significantly increased risks could be detected in FCCX compared to LLS patients, and the general population. Colorectal and endometrial cancer risks tended to be higher in LLS than in FCCX.ConclusionsThe characterisation of cancer risks in patients with LLS and FCCX is important to develop appropriate surveillance programmes for these specific intermediate risk groups. Larger prospective studies are needed to obtain more precise risk estimates.

The Effectiveness of Clinical Guidelines in the Diagnosis of Lynch Syndrome Compared to Microsatellite Instability and Immunohistochemistry Analyses in Southern Thailand

Objective: This study aims to assess the accuracy of Amsterdam II criteria (AMII) and Revised Bethesda Guidelines (RBG) compared to molecular tests in Thai patients.Material and Methods: One hundred eighty-one patients were enrolled. Demographic data and pathological features and locations of tumors were recorded. Family history of the patients was reviewed by AMII and RBG. Tissue samples were collected and molecular testing was tested by microsatellite instability (MSI) analysis and immunohistochemistry (IHC). Statistical analysis was used to estimate the sensitivity and specificity of AMII and RBG compared to molecular testing.Results: Of the patients, 2.8% fulfilled the AMII criteria and 28.1% met the RBG criteria. Molecular testing showed 16.57% and 13.8% of the samples lost at least 1 out of 4 mismatch repair (MMR) proteins in the IHC test. In addition, 10.5% of patients had both microsatellite instability high (MSI-H) and loss of protein MMR expression. The sensitivity and specificity of AMII were 6.7% and 98.0%, respectively, while for the RBG they were 70.0% and 82.1%, respectively.Conclusion: The present study suggests that for patients who complete the AMII, doctors should be highly suspicious of Lynch syndrome, due to its high specificity. The RBG is useful for screening for Lynch syndrome and the selection of individuals for further molecular testing.

A survey of the clinicopathological and molecular characteristics of patients with suspected Lynch syndrome in Latin America

BackgroundGenetic counselling and testing for Lynch syndrome (LS) have recently been introduced in several Latin America countries. We aimed to characterize the clinical, molecular and mismatch repair (MMR) variants spectrum of patients with suspected LS in Latin America.MethodsEleven LS hereditary cancer registries and 34 published LS databases were used to identify unrelated families that fulfilled the Amsterdam II (AMSII) criteria and/or the Bethesda guidelines or suggestive of a dominant colorectal (CRC) inheritance syndrome.ResultsWe performed a thorough investigation of 15 countries and identified 6 countries where germline genetic testing for LS is available and 3 countries where tumor testing is used in the LS diagnosis. The spectrum of pathogenic MMR variants included MLH1 up to 54%, MSH2 up to 43%, MSH6 up to 10%, PMS2 up to 3% and EPCAM up to 0.8%. The Latin America MMR spectrum is broad with a total of 220 different variants which 80% were private and 20% were recurrent. Frequent regions included exons 11 of MLH1 (15%), exon 3 and 7 of MSH2 (17 and 15%, respectively), exon 4 of MSH6 (65%), exons 11 and 13 of PMS2 (31% and 23%, respectively). Sixteen international founder variants in MLH1, MSH2 and MSH6 were identified and 41 (19%) variants have not previously been reported, thus representing novel genetic variants in the MMR genes. The AMSII criteria was the most used clinical criteria to identify pathogenic MMR carriers although microsatellite instability, immunohistochemistry and family history are still the primary methods in several countries where no genetic testing for LS is available yet.ConclusionThe Latin America LS pathogenic MMR variants spectrum included new variants, frequently altered genetic regions and potential founder effects, emphasizing the relevance implementing Lynch syndrome genetic testing and counseling in all of Latin America countries.

Prospective correlation between clinical and pathologic criteria identification of Lynch syndrome (LS) in endometrial carcinoma (EC) patients and relapse.

1543 Background: Prospective comparison of different methods for recognition of LS associated EC is lacking. Microsatellite instability (MSI) has been observed to be inconsistent as a prognostic factor in EC. The aim of this study was to analyze the impact of MSI and Mismatch Repair (MMR)-deficiency on LS identification and prognosis in a prospective series of EC treated in one single institution. Methods: Consecutive and prospective EC patients were included. Clinical data, family history of cancer and criteria for LS were evaluated. MSI and MMR protein expression were performed. When loss of MMR proteins and/or high MSI (MSI-H) was observed, complete sequencing and large genomic rearrangement analysis of germline MLH1, MSH2, MSH6 or PMS2 was done once MLH1 methylation was excluded. Results: Seventy-seven women diagnosed with EC were enrolled from 2009 to 2012 with a median age of 62 (31-87), 84% histological type I, 16% type II and FIGO stages I 83%, II 2.8%, III-IVA 7% and IVB 7%. Among which, 6.6% fulfilled revised Bethesda criteria (rBC), 5.3% criteria defined by the Society Gynecologic Oncology (&gt;20%-to-25% risk of LS) (SGO) and 5.3% Amsterdam II criteria (AII). Seventy-four underwent surgery with curative-intent. Tumor tissue was unavailable in 5 cases for molecular analysis. MSI-H was observed in16 cases (22%) and 18 (24%) had loss of expression of MLH1 (14), MSH2 (2), MSH6 (1) or PMS2 (1). Nine MLH1 hypermethylation, 10 K-RAS and no BRAF mutations were identified. Four (5.5%) pathogenic MMR germline mutations were recognized: 2 MSH2, one MSH6 and one PMS2. One patient (25%) with MSH6 mutation did not fulfil rBC, SGO nor AII criteria and was identified both by MSI-H and loss of MSH6 expression. Median follow-up was 23.4 (0.2-76.3) months. No correlation between MSI-H, MMR gene mutation and relapse was observed in stage I-IVA EC. Conclusions: Based on these results, rBC, AII and SGO criteria for identification of LS in EC do not identify 25% of germline MMR gene mutations. No correlation with relapse and MSI-H could be identified.

Patients With Colorectal and Renal Cell Carcinoma Diagnoses Appear to Be at Risk for Additional Malignancies

BackgroundSmall studies have demonstrated that patients who have both colorectal and renal cell carcinoma may be at increased risk for the development of additional malignancies. A possible genetic basis has been suggested. Our study describes the clinicopathologic features of these patients and clarifies the relationship of this cohort with Lynch syndrome (LS). MethodsPatients with primary CRC and RCC treated at our institution were identified. Medical records were reviewed for demographic and clinical information. Immunohistochemical staining for mismatch repair (MMR) proteins was performed on tumor tissue when possible. ResultsDuring the study period, 24,642 patients were treated for CRC and 7,366 were treated for RCC at our institution. One hundred seventy-nine patients had both diagnoses, with 101 patients eligible for inclusion in our cohort. Tumors were typically early stage. The 2 cancers presented as synchronous lesions in 42% of patients. Thirty-two patients had 1 additional primary malignancy, 7 patients had 2 additional primary malignancies, and 3 patients had 3 additional primary malignancies. No patient had a family history that met the Amsterdam II criteria (AC) for LS, but 50% had family members with 1 malignancy. One of 10 colorectal tumors analyzed for the absence of MMR protein expression demonstrated the absence of MSH6, but the corresponding RCC demonstrated intact expression of all 4 MMR proteins. ConclusionIt is rare for patients to be diagnosed with both CRC and RCC. The clinicopathologic features of this cohort and the results of immunohistochemical analysis performed on a sample of these patients do not suggest LS. However, the high rate of additional carcinomas suggests a need for careful follow-up. Multicenter longitudinal studies are warranted to further understand the natural history and possible genetic basis for this entity.

Prevalence of Alterations in DNA Mismatch Repair Genes in Patients With Young-Onset Colorectal Cancer

Direct germline analysis could be used to screen high-risk patients for mutations in DNA mismatch repair genes associated with Lynch Syndrome. We examined the prevalence of mutations in MLH1, MSH2, and MSH6 in a population-based sample of patients with young-onset (age <50 years) colorectal cancer (CRC). Young-onset CRC cases were randomly selected from 3 Colon Cancer Family Registry sites. DNA was extracted from peripheral blood leukocytes; MLH1, MSH2, and MSH6 were sequenced, and duplication and deletion analyses was performed for MLH1 and MSH2. Results were reported as deleterious or suspected deleterious, likely neutral, variant of uncertain significance, or no alteration detected. Germline data were compared to Amsterdam II criteria (ACII) and immunohistochemistry results in secondary analyses. Among 195 subjects, 11 had deleterious/suspected deleterious mutations (5.6%; 95% confidence interval [CI], 2.8%-9.9%), 12 had likely neutral alterations (6.2%; 95% CI, 3.2%-10.5%), 14 had variants of uncertain significance (7.2%; 95% CI, 4.0%-11.8%), 2 had a likely neutral alteration and a variant of uncertain significance (1.0%; 95% CI, 0.1%-3.7%), and 156 had no alteration detected (80.0%; 95% CI, 73.7%-85.4%). Sensitivity, specificity, and positive and negative predictive values for detecting deleterious/suspected deleterious mutations, based on ACII, were 36.4% (4/11), 96.7% (178/184), 40.0% (4/10), and 96.2% (178/185), respectively; based on immunohistochemistry these values were 85.7% (6/7), 91.9% (136/148), 33.3% (6/18), and 99.3% (136/137), respectively. In a population-based sample of young-onset CRC cases, germline mutations in MLH1, MSH, and/or MSH6 were more prevalent than reported for CRC patients overall. Because only about 5% of young-onset CRC cases had confirmed deleterious or suspected deleterious mutations, further comparative effectiveness research is needed to determine the most appropriate screening strategy for Lynch Syndrome in this high-risk group.

Taiwan hospital-based detection of Lynch syndrome distinguishes 2 types of microsatellite instabilities in colorectal cancers

With progress in techniques of molecular biology, the phenotypes and genotypes for Lynch syndrome are more diverse than thought previously. This hospital-based study estimated the incidence and molecular and clinicopathologic features of Lynch syndrome to modify the screening criteria for Taiwanese patients with colorectal cancer (CRC). A total of 561 CRC patients were enrolled. DNA was extracted from neoplasms, normal mucosa, and/or white blood cells for analyses of microsatellite instability (MSI), BRAF mutation, MLH1 methylation, and sequencing of MMR genes. Immunohistochemistry (IHC) staining for MMR proteins was done for cases that fulfilled revised Bethesda criteria and for high-frequency microsatellite instability (MSI-H) neoplasms. There were 136 (24.2%) and 10 (1.8%) cases that fulfilled the Revised Bethesda and Amsterdam II criteria (ACII), respectively. MSI-H was detected in 41 (7.3%), of which 32 showed abnormalities for > or = 1 MMR protein by IHC; low-frequency MSI (MSI-L) or microsatellite stable showed abnormal MSH2 staining in only 1 of 117 neoplasms. Thirteen (2.3%) cases had mutations in MMR genes with MLH1 (n = 10), MSH2 (n = 2), or MSH6 (n = 1). Of 13 Lynch syndrome cases, 3 (23.1%) and 11 (84.6%) fulfilled ACII and revised Bethesda criteria, respectively; 12 cases (93.3%) were MSI-H, and all had expression loss of > or = 1 MMR protein. Eight patients were >50 years old, 2 of whom did not fulfill revised Bethesda criteria. For MSI-H neoplasms without definite mutations, 72.4% and 44.8% showed MLH1 methylation and a BRAF (V599E) mutation, respectively. Lynch-associated CRC and sporadic MSI neoplasms shared similar clinicopathologic features. In Taiwan, the incidence of Lynch syndrome was 2.3% among the 561 CRC patients evaluated. For Taiwanese CRC patients who are younger than age 60 whether or not fulfilling the Bethesda criteria should receive MSI or IHC screening for identification of the Lynch syndrome.

Mismatch repair protein expression in Amsterdam II criteria-positive patients in Taiwan

Hereditary non-polyposis colorectal cancer (HNPCC) is characterized genetically by germline mutations in DNA mismatch repair (MMR) genes. Immunohistochemistry (IHC) has high sensitivity and specificity for identifying MMR-deficient tumours. This study investigated the clinical presentations and frequency of HNPCC in Taiwan by combined Amsterdam II criteria (AC-II) and IHC. In 1995-2003, 7108 patients with primary colorectal cancer registered in Chang Gung Memorial Hospital's Colorectal Cancer Registry were screened using AC-II. Tumour specimens were analysed for MMR protein expression by IHC, and relevant clinicopathological details were documented. Some 83 patients fulfilled the AC-II. Clinicopathologically, 43 patients (52 per cent) had proximal tumours, ten (12 per cent) had poorly differentiated cancers, 17 (20 per cent) had mucinous adenocarcinoma and 51 (61 per cent) had stage I-II tumours. Seventeen patients developed second primary colonic and extracolonic cancers over a mean 7.2-year follow-up. Immunohistochemically, 58 patients were MMR protein deficient. They had a significantly earlier age of onset (P < 0.001), more proximal tumour location (P = 0.002), less advanced tumour stage (P = 0.008) and more second primary cancers (P = 0.017) compared with MMR-competent patients. These data show significant differences in clinical features between MMR protein-deficient and MMR competent subgroups.

Efficiency of the revised Bethesda guidelines (2003) for the detection of mutations in mismatch repair genes in Austrian HNPCC patients

The clinical diagnosis of hereditary nonpolyposis colorectal cancer (HNPCC) is based on the Amsterdam II criteria (ACII). The purpose of using the Bethesda guidelines (BG) is to select tumours for microsatellite analysis. Recently, the modified Amsterdam criteria (ACmod) and Bethesda guidelines (BGmod) were proposed to simplify definitions. We evaluated the efficiency of the ACmod and BGmod to identify patients with germ-line mutations in MLH1 and MSH2 in 81 unrelated Austrian HNPCC families. Microsatellite (MS) analysis was performed in 55 tumours. The new criteria included more families than the old ones: BGmod, n = 81; BG, n = 72; ACmod, n = 52 and ACII, n = 35. The more stringent old criteria tended to show greater positive predictive value for association with a germ-line mutation than the corresponding new criteria: BGmod, 23%; BG, 26%; ACmod, 31% and ACII, 37%. The larger number of patients analysed in the ACmod group resulted in greater sensitivity compared to the ACII. The increased workload for BGmod was not associated with greater sensitivity. Microsatellite instability (MSI) significantly enhanced specificity in all subgroups. We recommend the use of the ACmod criteria to select patients for primary sequence analysis, when microsatellite analysis is not possible. If the BG are used, we suggest that BG be given preference over BGmod, as the former signify a lesser workload.