1. [Application of PMS2 and MSH6 double-antibody detection in screening of mismatch repair deficient tumors].
- Author
-
Wang CS, Zhang B, Sun Q, Yang J, Cui XB, and Wu HY
- Subjects
- Humans, Retrospective Studies, Stomach Neoplasms genetics, Stomach Neoplasms pathology, Stomach Neoplasms metabolism, Female, High-Throughput Nucleotide Sequencing, Biomarkers, Tumor genetics, Biomarkers, Tumor metabolism, Immunohistochemistry, Sensitivity and Specificity, MutL Protein Homolog 1 genetics, MutL Protein Homolog 1 metabolism, MutS Homolog 2 Protein genetics, MutS Homolog 2 Protein metabolism, Mismatch Repair Endonuclease PMS2 genetics, Mismatch Repair Endonuclease PMS2 metabolism, DNA-Binding Proteins genetics, DNA-Binding Proteins metabolism, Endometrial Neoplasms genetics, Endometrial Neoplasms pathology, Endometrial Neoplasms metabolism, Endometrial Neoplasms diagnosis, Colorectal Neoplasms genetics, Colorectal Neoplasms pathology, Colorectal Neoplasms diagnosis, Microsatellite Instability, DNA Mismatch Repair
- Abstract
Objective: To investigate whether the immunohistochemical results of two markers PMS2 and MSH6 (2-MMR) could replace the four markers MLH1, PMS2, MSH2 and MSH6 (4-MMR) to detect mismatch repair deficient (dMMR) cancers. Methods: A retrospective analysis was conducted with summary of immunohistochemical data from 7 867 cases of gastric cancer, colorectal cancer, endometrial cancer, and other diseases in the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, China, from March 2018 to March 2023. The consistency of 2-MMR and 4-MMR results was examined. Microsatellite instability (MSI) and next-generation sequencing (NGS) were performed in patients with specific phenotypes. Results: The Cohen κ values of 2-MMR and 4-MMR in gastric cancer, colorectal cancer, endometrial cancer and other diseases were 0.88, 0.99, 0.88 and 1.00, respectively. The overall consistency, sensitivity and specificity were 0.97, 99.6%, and 100.0%, respectively. Both 2-MMR and 4-MMR could detect the difference between various clinicopathological features. 24 (0.3%) of the 7 867 patients were found to have a special phenotype of MMR, and 6 of them were selected for MSI and NGS molecular testing. MSI analysis showed MSI-H in all cases, while NGS found that 5 of them had MMR-related gene mutations and 1 had POLE p.S297F mutation. Conclusions: Compared with 4-MMR, 2-MMR has high consistency, specificity and sensitivity. The cases with special phenotype only account for extremely low proportion. Therefore, 4-MMR may be replaced with 2-MMR in dMMR screening.
- Published
- 2025
- Full Text
- View/download PDF