Quantitative Evaluation of Lymphoid Reaction and CD8+ T Lymphocyte Count in Colorectal Carcinoma (CRC) and Its Association with Grading and Staging of CRC

Abstract

Introduction: Staging of colorectal carcinoma (CRC) is based on the depth of tumor invasion, presence or absence of regional lymph node involvement, distant metastases, and differentiation. It was observed in some studies that an increase in lymphocytic infiltrate in CRC is linked with better survival. Hence, the present study was undertaken for quantitative evaluation of lymphoid reaction and CD8+T lymphocyte count in CRC. Aims and Objectives: To evaluate the association between peritumoral lymphoid reaction (PTLR) and CD8+T lymphocyte infiltration with grading and staging of CRC. Materials and Methods: A cross-sectional, descriptive study on excised specimens of CRC received in the Department of Pathology from 2015 to 2020 was done. A total of 38 resected specimens of CRC diagnosed as adenocarcinoma on histopathology were evaluated for age, sex, tumor location, grading, and staging of the tumor. A quantitative evaluation of PTLR and CD8+ T lymphocyte marker score was done in all cases and was correlated with the grading and staging of CRC. Results: The mean age of patients in the present study was 52.8 years with male-to-female ratio of 1:1. The most common site was the proximal colon. The majority of the cases were moderately differentiated adenocarcinoma. Stage pT3 and pNo were the most common followed by stage pT2 and stage pN1. PTLR and CD8+ lymphocyte count were highest in well-differentiated adenocarcinoma, in stage pT1 and stage pN0. Conclusions: Significant association was noted between PTLR and CD8+T lymphocyte count with grading and staging, and hence these can be considered as prognostic markers in CRC.