MSI/MMR-deficient tumor diagnosis: Which standard for screening and for diagnosis? Diagnostic modalities for the colon and other sites: Differences between tumors.

MSI/MMR-deficient tumor diagnosis: Which standard for screening and for diagnosis? Diagnostic modalities for the colon and other sites: Differences between tumors. Bull Cancer. 2019 Jan 31;: Authors: Svrcek M, Lascols O, Cohen R, Collura A, Jonchère V, Fléjou JF, Buhard O, Duval A Abstract Microsatellite instability (MSI), which is caused by deficiency of the DNA mismatch repair (MMR) system, is the molecular abnormality observed in tumors associated with Lynch syndrome. Lynch syndrome represents one of the most frequent conditions of cancer predisposition in human, thus requiring specific care and genetic counseling. Moreover, research has recently focused increasingly on MMR deficiency due to its positive predictive value for the efficacy of immune checkpoints inhibitors (ICKi) in metastatic tumors, regardless of their primary origin. MSI has also been demonstrated to constitute an independent prognostic factor in several tumor types, being also associated with alternative response to chemotherapy. These observations have led many professional medical organizations to recommend universal screening of all newly diagnosed colorectal cancers for dMMR/MSI status and increasing evidence support the evaluation of MSI in all human tumors regardless of the cancer tissue of origin. Currently, two standard reference methods, namely immunohistochemistry and polymerase chain reaction, are recommended for the detection of dMMR/MSI status. The...
Source: Bulletin du Cancer - Category: Cancer & Oncology Authors: Tags: Bull Cancer Source Type: research