MMR status of colorectal carcinomas at a tertiary cancer care centre in Central India

Microsatellite instability (MSI) and mismatch repair (MMR) deficiency are important biomarkers in colorectal cancer (CRC) that have clinical implications for patient management and treatment. MMR deficiency can lead to MSI, which is characterized by alterations in the length of microsatellite DNA sequences. Clinical applications of MMR deficiency in colorectal adenocarcinoma are as a prognostic marker as well as Predictive marker for adjuvant chemotherapy and immunotherapy. To assess the MMR status of colorectal adenocarcinomas.: This was a retrospective study of 127 colorectal adenocarcinomas cases. All the samples were either biopsies or surgically resected tumor tissues from patients of Carcinoma Colon and rectum. Immunohistochemistry was performed on Roche Ventana Benchmark XT autostainer.: MLH-1, PMS2, MSH2 and MSH6 expression was retained in the tumor cells in 106 cases and it was lost in 21 cases. Among various clinicopathological variables, tumor site and AJCC pStage were found to be significantly associated with dMMR tumors. Patients of colorectal adenocarcinomas were benefited by MMR testing as it influenced the adjuvant treatment in all Stage IIA cases as well as all metastatic cases. Incorporating MMR testing into routine clinical practice can help optimize patient management and treatment strategies in CRC.