The impact of different adjuvant intravesical therapy methods on tumor biology in patients with high-risk non-muscle-invasive bladder cancer

INTRODUCTION: Expression level of the cell proliferation marker Ki-67 correlates with the degree of differentiation of tumor cells and stage in primary patients with non-muscle-invasive bladder cancer (NMIBC), but the marker is currently not used in assessing the efficacy of adjuvant intravesical therapy and risk stratification in patients with recurrent bladder tumors. MATERIAL AND METHODS: A retroprospective study included 107 patients with high-risk NMIBC; the patients were divided into 2 groups. The first group included patients who received adjuvant therapy after transurethral resection of the bladder using the Bacillus Calmette-Guérin (BCG) vaccine (BCG therapy group; n = 54), the second group consisted of patients who received hyperthermic intravesical chemotherapy (HIVEC(®) therapy group; n = 53) using the device for local hyperthermia Combat BRS HIVEC(®). RESULTS: Tumor recurrences were recorded in 21 (39%) patients receiving intravesical BCG therapy and in 9 (17%) patients after intravesical hyperthermic chemotherapy (p = 0.012). The expression level of Ki-67 in primary tumors did not differ; in recurrent tumors it was significantly different in both groups (32.05 ±13.80 vs 11.00 ± 6.86). The frequency of recurrence-free survival (RFS) in patients receiving chemohyperthermia was significantly higher than in patients after the BCG therapy (log-rank test result: p = 0.048). CONCLUSIONS: Assessment of Ki-67 expression in recurrent tumors can be a criterion for the effectiveness of intravesical bladder-preserving treatment. The use of hyperthermic chemotherapy can reduce the number of radical cystectomies in a separate group of patients with NMIBC.