A Retrospective Cohort Study Assessing the Prognostic Significance of Tumor-Associated Macrophages (TAMs) in Gastric Cancer in the Indian Population.

Background & Objective: Tumor-associated macrophages (TAMs) are key components of the tumor microenvironment and may hold prognostic significance in gastric cancer (GC). Limited data are available from the Indian population. Methods: In this retrospective study, CD68 immunohistochemistry was performed on 60 surgically resected gastric adenocarcinomas. TAM density was quantified as the average number of positive cells per high-power field and categorised into low and high groups using a cutoff of 50 cells/HPF. Associations with clinicopathological features were analysed using chi-square and logistic regression. Results: High TAM density was observed in 70% of cases and was significantly associated with larger tumor size (p = 0.05), increased tumor-infiltrating lymphocytes (p = 0.021), advanced pT stage (p = 0.007), lymph node metastasis (p < 0.001), and advanced clinical stage (p = 0.009). On multivariate analysis, lymph node metastasis remained an independent predictor of high TAM density (adjusted OR = 2.5; 95% CI: 1.02-6.2; p = 0.04).