Towards improved detection and management of Lynch Syndrome

Lynch syndrome is the most common hereditary colorectal cancer syndrome, responsible for 3-5% of all colorectal cancer (CRC) cases. In addition, tumors of the endometrium, ovaries, stomach, small bowel, biliary tract, urinary tract, skin and brain occur at higher frequencies compared to the general population. Mutations in at least four different mismatch repair (MMR) genes, including MLH1, MSH2, MSH6 and PMS2, are the underlying defect in Lynch syndrome. The introduction in chapter 2 gives a general overview of different aspects of Lynch syndrome. Clinical features, cancer risks, diagnostic strategies, surveillance and management of Lynch syndrome are discussed. The identification of Lynch syndrome is still suboptimal, mainly due to the lack of specific diagnostic features. Early ident

Mutation prediction models in Lynch syndrome: evaluation in a clinical genetic setting

Background/aims: The identification of Lynch syndrome is hampered by the absence of specific diagnostic features and underutilization of genetic testing. Prediction models have therefore been developed, but they have not been validated for a clinical genetic setting. The aim of the present study was to evaluate the usefulness of currently available prediction models. METHODS: We collected data of 321 index probands who were referred to the department of Clinical Genetics of the Erasmus Medical Center because of a family history of colorectal cancer. These data were used as input for five previously published models. External validity was assessed by discriminative ability (AUC: area under the receiver operating characteristic curve) and calibration. For further insight, predicted probabilities were categorized with cut-offs of 5%, 10%, 20% and 40%. Furthermore, costs of different testing strategies were related to the number of extra detected mutation carriers. RESULTS: Of the 321 index probands, 66 harboured a germline mutation. All models discriminated well between high risk and low risk index probands (AUC: 0.82-0.84). Calibration was well for the Premm1,2 and Edinburgh model, but poor for the other models. Cut-offs could be found for the prediction models where costs could be saved while missing only few mutations. CONCLUSIONS: The Edinburgh and Premm1,2 model were the models with the best performance for an intermediate to high-risk setting. These models may well be of use in clinical practice to select patients for further testing of mismatch repair gene mutations

Cancer risk in MLH1, MSH2 and MSH6 mutation carriers; different risk profiles may influence clinical management

Background: Lynch syndrome (LS) is associated with a high risk for colorectal cancer (CRC) and extracolonic malignancies, such as endometrial carcinoma (EC). The risk is dependent of the affected mismatch repair gene. The aim of the present study was to calculate the cumulative risk of LS related cancers in proven MLH1, MSH2 and MSH6 mutation carriers.Methods: The studypopulation consisted out of 67 proven LS families. Clinical information including mutation status and tumour diagnosis was collected. Cumulative risks were calculated and compared using Kaplan Meier survival analysis.Results: MSH6 mutation carriers, both males and females had the lowest risk for developing CRC at age 70 years, 54% and 30% respectively and the age of onset was delayed by 3-5 years in males. With respect to endometrial carcinoma, female MSH6 mutation carriers had the highest risk at age 70 years (61%) compared to MLH1 (25%) and MSH2 (49%). Also, the age of EC onset was delayed by 5-10 years in comparison with MLH1 and MSH2.Conclusions: Although the cumulative lifetime risk of LS related cancer is similar, MLH1, MSH2 and MSH6 mutations seem to cause distinguishable cancer risk profiles. Female MSH6 mutation carriers have a lower CRC risk and a higher risk for developing endometrial carcinoma. As a consequence, surveillance colonoscopy starting at age 30 years instead of 20-25 years is more suitable. Also, prophylactic hysterectomy may be more indicated in female MSH6 mutation carriers compared to MLH1 and MSH2 mutation carriers

Systematic Review with Meta-Analysis: Diagnostic Accuracy of Pro-C3 for Hepatic Fibrosis in Patients with Non-Alcoholic Fatty Liver Disease

The prevalence and severity of non-alcoholic fatty liver disease (NAFLD) is increasing, yet adequately validated tests for care paths are limited and non-invasive markers of disease progression are urgently needed. The aim of this work was to summarize the performance of Pro-C3, a biomarker of active fibrogenesis, in detecting significant fibrosis (F ≥ 2), advanced fibrosis (F ≥ 3), cirrhosis (F4) and non-alcoholic steatohepatitis (NASH) in patients with NAFLD. A sensitive search of five databases was performed in July 2021. Studies reporting Pro-C3 measurements and liver histology in adults with NAFLD without co-existing liver diseases were eligible. Meta-analysis was conducted by applying a bivariate random effects model to produce summary estimates of Pro-C3 accuracy. From 35 evaluated reports, eight studies met our inclusion criteria; 1568 patients were included in our meta-analysis of significant fibrosis and 2058 in that of advanced fibrosis. The area under the summary curve was 0.81 (95% CI 0.77–0.84) in detecting significant fibrosis and 0.79 (95% CI 0.73–0.82) for advanced fibrosis. Our results support Pro-C3 as an important candidate biomarker for non-invasive assessment of liver fibrosis in NAFLD. Further direct comparisons with currently recommended non-invasive tests will demonstrate whether Pro-C3 panels can outperform these tests, and improve care paths for patients with NAFLD

Reversible severe hepatitis in anorexia nervosa: a case report and overview

Mildly elevated transaminases are often observed in anorexia nervosa patients, but severe hepatitis is less common. We suggest that hypoperfusion is the pathogenetic factor that causes severe hepatitis in a patient with a very poor nutritional status and present an overview of previous case reports. In our patient, early initiation of intravenous fluids resulted in rapid recovery of the liver test abnormalities, despite minimal oral caloric intake, the refusal of enteral feeding and the development of a hypoglycemic coma. Two months after admission, transaminases had normalized. Reversible severe hepatitis has been described in most of the cases, with only one anorexia nervosa-related fatal hepatitis. In general, both adequate hydration and gradual enteral feeding with monitoring of electrolytes are essential in the management of anorexia patients with severe hepatitis

Outcomes of push and pull percutaneous endoscopic gastrostomy placements in 854 patients: A single-center study

Background and Aims: Percutaneous endoscopic gastrostomy (PEG) is indicated for prolonged enteral nutrition. This study aimed to analyze the outcome and to identify potential risk factors for complications in PEG procedures. Methods: A single-center retrospective analysis of the performed PEG procedures during the period January 2010 till January 2020. Results: A PEG placement procedure was performed in 854 patients (64.1% male) and was successful in 833 (97.5%). In total, 513 push (61.6%) and 320 pull (38.6%) PEGs were placed. The mean age was 60.7 years, and the median follow-up was 267 days. The push PEG was associated with peri-procedural bleeding (P = 0.002) and tube dislodgements (P < 0.001), while the pull PEG was significantly associated with buried bumpers (P < 0.001), infected placement sites (P = 0.019), and granulation tissue formation (P = 0.044). The PEG-related mortality rate was 0.2%, but the overall 30-day mortality was 4.0%. Conclusion: The current study showed that the push and pull PEG placements are both safe and feasible procedures, with a low PEG-related mortality. Buried bumpers, infected placement sites, and granulation tissue formation are more often seen in the pull PEG, while the push PEG is associated with periprocedural bleeding and tube dislodgements. These complications should be taken into account and there is a need for a prospective trial to identify superiority between the PEG methods