Yang W, et al. - In order to provide additional insights into the role of calcium in colorectal carcinogenesis, researchers performed this prospective cohort study examining the correlation between calcium intake and colorectal cancer risk according to tumor immunity status. They performed IHC and computer-assisted image analysis 736 cancer cases that developed among 136,249 individuals in two cohorts to determine the densities of tumor-infiltrating T-cell subsets [CD3+, CD8+, CD45RO (PTPRC)+, or FOXP3+ cell]. A multivariable HR of 0.55 was observed in correlation with total calcium intake for CD8+ T-cell–low but not for CD8+ T-cell–high tumors. Similarly, for low vs high T-cell–infiltrated tumors, they noted the corresponding HRs for calcium of 0.63 and 0.89 for CD3+; 0.58 and 1.04 for CD45RO+; and 0.56 and 1.10 for FOXP3+, although there were no statistically significant differences by subtypes defined by T-cell density. These findings suggest that calcium may have a role in cancer immunoprevention via modulation of T-cell function.