Prognostic Significance of Regulatory CD25+ T Cells in Bladder Cancer: An Immunohistochemical Analysis.

OBJECTIVE

Tumor-infiltrating lymphocytes (TILs) have been shown to predict outcomes in several cancers. This study aimed to evaluate the density and location of regulatory T cells (Tregs) using immunohistochemistry (IHC) in urothelial carcinomas (UC) of the bladder and to assess their prognostic value.

MATERIAL AND

METHODS

We have retrospectively collected all cases of UC of the bladder infiltrating at least the lamina propria, diagnosed in our pathology department between 2011-2021. Specimens were stained for CD3 and CD25. TILs were assessed separately in the tumor core and the stroma. The median TIL count was used as a cut-off to classify cases into low- or high-density groups.

RESULTS

A total of 30 cases were included in the study. The median age of the patients was 65 years, with a male-to-female ratio of 9:1. The distribution of TILs was heterogeneous across locations among patients. CD3+ (p=0.035) and CD25+ (p=0.051) TILs were predominantly observed in the stroma. The density of CD25+ and CD3+ TILs were not associated with clinicopathological features. Multivariate analysis revealed that advanced histological stage and a high density of regulatory CD25+ T lymphocytes were predictive factors of poorer event-free survival (respectively p=0.041 and p=0.052).

CONCLUSION

Regulatory T cells appear to predict worse survival outcomes. Further studies are needed to confirm their prognostic value.