Targeted next generation sequencing screening of Lynch syndrome in Tunisian population

In this study we aimed to identify the underlying genetic cause in 32 patients with early onset CRC and/or a positive family history. Of twenty-four patients ’ tumor or biopsies could be analyzed with immunohistochemical staining to detect loss of expression of one of the MMR proteins. Ten tumors showed loss of expression, of which one tumor was from a patient where a germline pathogenicMSH2 variant was detected previously with Sanger sequencing. Next generation sequencing of the MMR,POLE andPOLD1 genes was performed in leukocyte and tumor DNA of the remaining nine patients, as well as in two patients with MMR-proficient tumors, but with severe family history. In six of 11 patients a germline variant was detected inMLH1 (n  = 5) orMSH2 (n  = 1). Two of six patients were from the same family and both were found to carry a novel in-frameMLH1 deletion, predicted to affect MLH1 function. AllMLH1 variant carriers had loss of heterozygosity with retention of the variant in the tumors, while a somatic pathogenic variant was detected in the patient with the germlineMSH2 variant.
Source: Familial Cancer - Category: Cancer & Oncology Source Type: research

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ConclusionTo optimize targeting and visualization of the surgical field in right pelvic sidewall/paracolic gutter, robotic arms can be placed in a straight line from above the pubic symphysis extending to the left subcostal line and between the midline vertical and midclavicular lines. Robotic tumor debulking should be considered in selected patients with recurrent ovarian cancer who present with oligo-metastatic disease, in the absence of carcinomatosis.
Source: Journal of Minimally Invasive Gynecology - Category: OBGYN Source Type: research
Tougeron Tumor DNA mismatch repair (MMR) deficiency testing is important to the identification of Lynch syndrome and decision making regarding adjuvant chemotherapy in stage II colorectal cancer (CRC) and has become an indispensable test in metastatic tumors due to the high efficacy of immune checkpoint inhibitor (ICI) in deficient MMR (dMMR) tumors. CRCs greatly benefit from this testing as approximately 15% of them are dMMR but only 3% to 5% are at a metastatic stage. MMR status can be determined by two different methods, microsatellite instability (MSI) testing on tumor DNA, and immunohistochemistry of the MMR pro...
Source: Cancers - Category: Cancer & Oncology Authors: Tags: Review Source Type: research
AbstractBackgroundWe previously reported that in pathogenic mismatch repair (path_MMR) variant carriers, the incidence of colorectal cancer (CRC) was not reduced when colonoscopy was undertaken more frequently than once every 3 years, and that CRC stage and interval since last colonoscopy were not correlated.MethodsThe Prospective Lynch Syndrome Database (PLSD) that records outcomes of surveillance was examined to determine survival after colon cancer in relation to the time since previous colonoscopy and pathological stage. Onlypath_MMR variants scored by the InSiGHT variant database as class 4 or 5 (clinically actionable...
Source: Hereditary Cancer in Clinical Practice - Category: Cancer & Oncology Source Type: research
CONCLUSIONS: Universal tumour testing strategies for guiding germline genetic testing of people with incident CRC for LS in Australia are likely to be cost-effective compared with no testing. Universal germline gene panel testing would not currently be cost-effective. PMID: 31595523 [PubMed - as supplied by publisher]
Source: Medical Journal of Australia - Category: General Medicine Tags: Med J Aust Source Type: research
Endoscopy DOI: 10.1055/a-1016-4977ESGE recommends that individuals with Lynch syndrome should be followed in dedicated units that practice monitoring of compliance and endoscopic performance measures.Strong recommendation, low quality evidence, level of agreement 100 %.ESGE recommends starting colonoscopy surveillance at the age of 25 years for MLH1 and MSH2 mutation carriers and at the age of 35 years for MSH6 and PMS2 mutation carriers.Strong recommendation, moderate quality evidence, level of agreement 100 %. ESGE recommends the routine use of high-definition endoscopy systems in individuals with Lynch syndrome. Str...
Source: Endoscopy - Category: Gastroenterology Authors: Tags: Guideline Source Type: research
ConclusionsResults of the Idylla ™ MSI Assay were highly concordant with results of routine tests and lower failure rates were observed. Further advantages are the lack of need for matched normal tissue, the low dependence on pre-analytical conditions, the simplified workflow, the short turnaround times, the automated result inte rpretation, and the very limited hands-on work.Editorial acknowledgementTeams involved in the MSI, Idylla MSI Assay, Colon Rectal Cancer, Multicenter Study.Legal entity responsible for the studyIrblleida.FundingBiocartis.DisclosureX. Matias-guiu: Non-remunerated activity/ies: Biocartis.
Source: Annals of Oncology - Category: Cancer & Oncology Source Type: research
British Journal of Cancer, Published online: 25 September 2019; doi:10.1038/s41416-019-0580-9Type 2 diabetes mellitus, blood cholesterol, triglyceride and colorectal cancer risk in Lynch syndrome
Source: British Journal of Cancer - Category: Cancer & Oncology Authors: Source Type: research
Abstract About 5% of colorectal cancer (CRC) cases occurred in the context of an underlying hereditary predisposition syndrome. Lynch syndrome is the main causes of hereditary CRC but is also associated with a higher risk of other cancers (such as endometrial cancer and ovarian cancer). It is the consequence of constitutional mutation in a MisMatch Repair (MMR) gene, involved in DNA repair: MLH1, MSH2, MSH6 or PMS2; or of the EPCAM gene (MSH2 promotor). If a mutation predisposing to Lynch Syndrome is identified in an individual, special monitoring should be initiated, adapted to estimated cancer risk. Clinical cri...
Source: Presse Medicale - Category: General Medicine Authors: Tags: Presse Med Source Type: research
ConclusionFurther studies should be conducted to provide new insights about survival of colorectal carcinoma in Lynch syndrome, as well as the therapeutic alternatives for this neoplasia.ResumoIntroduçãoO carcinoma colorretal é a terceira neoplasia mais prevalente no mundo, bem como a segunda causa de morte por câncer. A maioria destas neoplasias são esporádicas, devidas a mutações somáticas, mas cerca de 15% são hereditárias como a síndrome de Lynch ou Hereditary Nonpolyposis Colorectal Cancer (HNPCC). Apesar de ser a mesma neoplasia, esta ...
Source: Journal of Coloproctology - Category: Gastroenterology Source Type: research
Dye-based pancolonic chromoendoscopy is recommended for colorectal cancer surveillance in patients with Lynch syndrome. However, there is scarce evidence to support its superiority to high-definition white-light endoscopy. We performed a prospective study assess whether in the hands of high detecting colonoscopists, high-definition, white-light endoscopy is non-inferior to pancolonic chromoendoscopy for detection of adenomas in patients with Lynch syndrome.
Source: Gastroenterology - Category: Gastroenterology Authors: Source Type: research
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