作者: Erika Hissong , Elizabeth P. Crowe , Rhonda K. Yantiss , Yao-Tseng Chen
DOI: 10.1038/S41379-018-0094-7
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摘要: Results of DNA mismatch repair testing are used to detect Lynch syndrome and have prognostic therapeutic implications among patients with sporadic colorectal carcinomas. Immunohistochemistry for proteins (MLH1, PMS2, MSH2, MSH6) PCR microsatellite instability two established methods assessing function. Older literature suggested a discordance rate approximately 5% between these assays, leading some institutions perform dual on all cases. Although universal is now recommended by multiple professional organizations, none provide guidelines regarding preferred assays. We surveyed 96 academic nonacademic assess screening practices evaluated rates immunohistochemistry 809 cancers tested in our own institution. Our survey demonstrated no significant differences respect strategies. Eighty six percent performed screening, usually (76%) employed initial biopsy samples. Only 20% PCR; were mostly that both (p < 0.01 compared the groups). Loss MLH1/PMS2 staining was often (90%) followed either BRAF mutational analysis or MLH1 methylation 24% adhered WHO recommendations assign histologic grade based status. found only 3 cases (0.4%) discordant results practice: 1 reflected decreased MSH-6 neoadjuvantly treated stable tumor, MLH1-deficient tumor showed diminished internal control, case an error molecular laboratory. Overall, extremely low status would suggest as single test. can be reserved show equivocal immunostaining patterns.