RT Journal Article SR Electronic T1 Prediction Model for Gastric Cancer With DNA Mismatch Repair Deficiency JF Anticancer Research JO Anticancer Res FD International Institute of Anticancer Research SP 975 OP 982 DO 10.21873/anticanres.14851 VO 41 IS 2 A1 OKIHIDE SUZUKI A1 TATSURO YAMAGUCHI A1 MINORU FUKUCHI A1 ERITO MOCHIKI A1 TOMIO ARAI A1 KIWAMU AKAGI A1 HIDEYUKI ISHIDA YR 2021 UL http://ar.iiarjournals.org/content/41/2/975.abstract AB Background/Aim: DNA mismatch repair (MMR) deficiency has received increasing attention as a biomarker of anti-PD-1 treatments of solid tumors including gastric cancer (GC). However, efficient screening has not been established. Patients and Methods: A total of 513 patients were tested for the expression of MMR proteins by immunohistochemistry to identify MMR deficient GC. Development of a prediction model was attempted using the common clinicopathological features. Results: In total, 11% (57/513) of the patients showed loss of expression of either one or more MMR proteins (MMR protein deficiency; MMR-D). Multivariate analysis demonstrated that age (≥70 years), sex (female), tumor location (lower 1/3), depth invasion (low, T1/T2/T3), and absence of distant metastasis were significantly independent predictive factors of MMR-D GCs. The MMR-D GC probability estimated by the prediction model ranged from 0.4% to 62.2%, and the area under the curve of the receiver operating characteristics curve was 0.82 (95% confidence interval=0.75-0.87). Conclusion: Our prediction model can sufficiently and efficiently identify MMR-D GCs using clinical features.