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Source at https://doi.org/10.1007/s10689-018-0072-8. Familial adenomatous polyposis (FAP) is usually caused by germline mutations in the adenomatous polyposis coli (APC) gene. The classic form is characterized by hundreds to thousands of adenomas in the colorectum and early onset colorectal cancer (CRC) if left untreated. FAP is also associated with multiple extra-colonic manifestations such as gastroduodenal polyps, osteomas, epidermoid cysts, fibromas and desmoids. Most desmoid tumours in FAP patients occur intra-abdominally. Approximately 15–20% of the APC mutations are de novo mutations. Somatic mosaicism has been reported in some sporadic cases of polyposis but is probably an underestimated cause of the disease. This case report presents the detection of a mosaic APC mutation in a 26-year-old woman who as a child had been diagnosed with desmoid type fibromatosis. FAP was suggested when she presented with extensive extra abdominal fibromatosis. Our findings indicate that APC mutations may be suspected in patients presenting with a desmoid regardless of its location. If there is clinical evidence that the patient has FAP, adenomas and colonic mucosa in addition to leukocyte DNA should be included in the screening, preferably using methods that are more sensitive than Sanger sequencing.

Item does not contain fulltext Familial colorectal cancer (CRC) accounts for 10-15% of all CRCs. In about 5% of all cases, CRC is associated with a highly penetrant dominant inherited syndrome. The most common inherited form of non-polyposis CRC is the Lynch syndrome which is responsible for about 2-4% of all cases. Surveillance of individuals at high risk for CRC prevents the development of advanced CRC. About 1 million individuals in Western Europe are at risk for Lynch syndrome. We performed a survey to evaluate the strategies currently used to identify individuals at high risk for CRC in 14 Western European countries. Questionnaires were distributed amongst members of a European collaborative group of experts that aims to improve the prognosis of families with hereditary CRC. The survey showed that in all countries obtaining a family history followed by referral to clinical genetics centres of suspected cases was the main strategy to identify familial and hereditary CRC. In five out of seven countries with a (regional or national) CRC population screening program, attention was paid in the program to the detection of familial CRC. In only one country were special campaigns organized to increase the awareness of familial CRC among the general population. In almost all countries, the family history is assessed when a patient visits a general practitioner or hospital. However, the quality of family history taking was felt to be rather poor. Microsatellite instability testing (MSI) or immunohistochemical analysis (IHC) of CRC are usually recommended as tools to select high-risk patients for genetic testing and are performed in most countries in patients suspected of Lynch syndrome. In one country, IHC was recommended in all new cases of CRC. In most countries there are no specific programs on cancer genetics in the teaching curriculum for medical doctors. In conclusion, the outcome of this survey and the discussions within an European expert group may be used to improve the strategies to identify individuals at high risk of CRC. More attention should be given to increasing the awareness of the general population of hereditary CRC. Immunohistochemical analysis or MSI-analysis of all CRCs may be an effective tool for identifying all Lynch syndrome families. The cost-effectiveness of this approach should be further evaluated. All countries with a CRC population screening program should obtain a full family history as part of patient assessment. 01 juni 2010

Endometrial cancer is frequent in MMR-mutation carriers. Estimates of annual incidence rates have, however, been based on retrospective studies. The purpose of our study was to prospectively assess the incidence rates of endometrial cancer in women either having a mutation in one of the four MMR genes MLH1, MSH2, MSH6 or PMS2 (Mut+) or belonging to families meeting the revised Amsterdam criteria in which no MMR mutation was detected (Ams+). Eight out of 80 Mut+ (10%) contracted invasive endometrial cancer compared to 1/171 (0.6%) of the Ams+ (P = 0.0006). The annual incidence rate after first control was 2.5% in Mut+ and 0.2% in Ams+. Two of the 8 Mut+ women (25%) had synchronous gynaecological tumours. The numbers included did not allow for firm conclusions, but the results are in keeping with the notion that the inherited colon-endometrial cancer syndrome may be restricted to carriers of MMR mutations.

Hereditary nonpolyposis colorectal cancer (HNPCC) may be caused by germline truncating mutations in DNA mismatch repair (MMR) genes. Whether or not missense or inframe mutations are disease-associated has become a practical clinical problem, because predictive genetic testing is employed to select high-risk persons for clinical examinations. Clinical examinations may reveal polyps to be removed and prevent cancer. One large kindred applying for health care had a N596del mutation in the MSH2 gene. The aim of this study was to determine whether or not the inframe mutation in this family was associated with disease, and to examine the tumours for presence of the MSH2 protein by immunohistochemistry. We demonstrated that the mutation was linked to disease with lod score 5.7 in the family, and all examined, but one manifest cancer, lacked the MSH2 protein.

Background and aims: Hereditary non-polyposis colorectal cancer (HNPCC) may be caused by mutations in the mismatch repair (MMR) genes MLH1, MSH2 or MSH6. Family history (Amsterdam criteria) has traditionally been used to select patients for mutation testing. It has been demonstrated that germline mutations in the MMR genes are associated with lack of the corresponding gene product as assessed with immunohistochemistry (IHC) in tumour specimens. The aim of the study was to assess the value of the Amsterdam criteria II and IHC in predicting germline mutations. Methods: Fifty-six families that were previously tested for MLH1, MSH2 and MSH6 mutations were selected for this study. All pedigrees were extended and verified and the families were scored according to the original (I) and the revised Amsterdam criteria (II). The probabilities for MLH1 and MSH2 mutations were calculated by logistic regression. In addition, all available tumour material from indexed family members was examined by IHC for the presence of the three gene products. Results: Three out of seven (39%) families where the mutation could be identified complied with the Amsterdam criteria I, while all seven (100%) met the Amsterdam criteria II. All families carrying a MLH1 or MSH2 mutation had > 15% calculated probability of finding a mutation. Tumours from all seven mutation carriers lacked the immunohistochemical expression of the corresponding MMR gene. Conclusion: The results indicate that the Amsterdam criteria II in combination with immunohistochemistry of the mismatch repair proteins in tumours may be a cost-effective approach to select families for mutation analysis.

Aim: To examine psychological distress in women at risk of familial breast–ovarian cancer (FBOC) or hereditary non-polyposis colorectal cancer (HNPCC) with absence of demonstrated mutations in the family (unknown mutation).Materials and methods: Two-hundred and fifty three consecutive women at risk of FBOC and 77 at risk of HNPCC and with no present or past history of cancer. They were aware of their risk and had received genetic counseling. Comparisons were made between these two groups, normal controls, and women who were identified to be BRCA1 mutation carriers. The questionnaires Beck Hopelessness Scale (BHS), General Health Questionnaire (GHQ-28), Hospital Anxiety and Depression Scale (HADS) and Impact of Event Scale (IES) were employed to assess psychological distress.Results: No significant differences concerning psychological distress were observed between women with FBOC and women with HNPCC. Compared to mutation carriers for BRCA1, the level of anxiety and depression was significantly higher in the FBOC group with absence of demonstrated mutation. Compared to normal controls, the level of anxiety was higher, while the level of depression was lower in the groups with unknown mutation.Conclusions: Women in the absence of demonstrated mutations have higher anxiety and depression levels than women with known mutation-carrier status. Access to genetic testing may be of psychologically benefit to women at risk for FBOC or HNPCC.

Hereditary nonpolyposis colorectal cancer (HNPCC) may be caused by germline truncating mutations in DNA mismatch repair (MMR) genes. Whether or not missense or inframe mutations are disease-associated has become a practical clinical problem, because predictive genetic testing is employed to select high-risk persons for clinical examinations. Clinical examinations may reveal polyps to be removed and prevent cancer. One large kindred applying for health care had a N596del mutation in the MSH2 gene. The aim of this study was to determine whether or not the inframe mutation in this family was associated with disease, and to examine the tumours for presence of the MSH2 protein by immunohistochemistry. We demonstrated that the mutation was linked to disease with lod score 5.7 in the family, and all examined, but one manifest cancer, lacked the MSH2 protein.

Hereditary non-polyposis colorectal cancer (HNPCC) may be caused by mutations in the mismatch repair (MMR) genes MLH1, MSH2 or MSH6. Family history (Amsterdam criteria) has traditionally been used to select patients for mutation testing. It has been demonstrated that germline mutations in the MMR genes are associated with lack of the corresponding gene product as assessed with immunohistochemistry (IHC) in tumour specimens. The aim of the study was to assess the value of the Amsterdam criteria II and IHC in predicting germline mutations.Fifty-six families that were previously tested for MLH1, MSH2 and MSH6 mutations were selected for this study. All pedigrees were extended and verified and the families were scored according to the original (I) and the revised Amsterdam criteria (II). The probabilities for MLH1 and MSH2 mutations were calculated by logistic regression. In addition, all available tumour material from indexed family members was examined by IHC for the presence of the three gene products.Three out of seven (39%) families where the mutation could be identified complied with the Amsterdam criteria I, while all seven (100%) met the Amsterdam criteria II. All families carrying a MLH1 or MSH2 mutation had15% calculated probability of finding a mutation. Tumours from all seven mutation carriers lacked the immunohistochemical expression of the corresponding MMR gene.The results indicate that the Amsterdam criteria II in combination with immunohistochemistry of the mismatch repair proteins in tumours may be a cost-effective approach to select families for mutation analysis.