A prognostic score based on B cell and plasma cell densities compared to T cell densities in colorectal cancer.

Purpose: The purpose of this study was to compare a B cell/plasma cell-based scoring system to T cell score and evaluate their prognostic value in colorectal cancer.

Methods: We used immunohistochemistry to analyze the expression of CD20, CD138, CD3, and CD8 in 221 colorectal cancer patients. CD20+ B cell and CD138+ plasma cell densities in the tumor center and invasive margin were calculated and converted into a B cell/plasma cell score. T cell score was defined similarly, using CD3+ and CD8+ T cell densities. Their associations with tumor and patient characteristics and survival were analyzed.

Results: Kaplan-Meier analysis showed a high B cell/plasma cell score was associated with a tendency towards longer survival (p = 0.089), but no statistically significant association was found. High T cell score associated with longer cancer-specific survival in Kaplan-Meier analysis and multivariable Cox regression analysis (p < 0.001). Additionally, high T cell score associated with lower disease stage (p < 0.001) and lesser lymphovascular invasion (p = 0.020).

Conclusions: High T cell score is associated with longer survival and clinicopathological factors typical to less aggressive tumors. This study did not support the additional prognostic value of B cell/plasma cell quantification.