The impact of CD47 and CS163 expressions on the efficacy of intravesical bacillus calmette-guerin therapy in non-muscle invasive bladder cancer

Aim: Intravesical Bacillus Calmette–Guérin (BCG) immunotherapy is a well-established treatment for preventing recurrence and progression in non-muscle invasive bladder cancer (NMIBC); however, its efficacy is not universal among all patients. Therefore, biomarkers capable of predicting treatment success are needed. This study aimed to investigate the inluence of CD47 and CD163 expression levels on recurrence and progression in NMIBC patients. Material and Method: A total of 110 patients newly diagnosed with NMIBC and treated with intravesical BCG therapy between 2015 and 2022 at Balıkesir University Health Application and Research Hospital, who met the inclusion criteria, were included in the study. The patients' demographic and clinical characteristics, as well as the histopathological features of their tumors, were retrospectively reviewed and recorded. CD47 and CD163 expressions in tissue blocks obtained from TUR-BT (transurethral resection of bladder tumor) materials were analyzed using immunohistochemical (IHC) methods by a single pathologist. Comparisons between groups were performed using the T-test for numerical variables and the chi-square test for categorical variables. Kaplan-Meier analysis was used for survival analysis, with a p-value of <0.05 considered statistically significant. Results: The mean age of the patients was 68.8 years. Among the included patients, 16 had TaHG, 42 had T1LG, and 52 had T1HG tumor pathology. A complete response to intravesical BCG therapy was observed in 74 patients (67.3%). Of the 36 patients with BCG failure, 10 experienced BCG-relapse, 14 were classified as BCG-refractory, and 12 progressed to muscle-invasive bladder cancer. CD47 expression levels were significantly higher in high-grade (HG) tumors compared to low-grade (LG) tumors (p<0.001), while no significant differences were observed in CD163 expression levels. No differences in CD47 or CD163 expression levels were found between the Ta and T1 groups. Patients with high CD163 expression intensity experienced significantly more frequent BCG failures (p=0.004), whereas no statistically significant differences were observed between CD47 expression groups in terms of BCG failure. Survival analysis revealed that CD47 expression was not associated with survival outcomes. However, patients with high CD163 expression intensity had significantly lower recurrence-free survival rates (p=0.004). Conclusion: In NMIBC patients treated with intravesical BCG therapy, high CD163 expression was associated with shorter recurrence-free survival. In contrast, although CD47 overexpression was more common in patients with high tumor grades, it did not significantly impact recurrence or progression rates.