Systematic Review of the Role of BCG in the Treatment of Urothelial Carcinoma of the Prostatic Urethra

BACKGROUND: In patients with non-invasive urothelial carcinoma of the prostatic urethra (PUC), treatment with Bacillus Calmette-Guérin (BCG) could be beneficial. OBJECTIVE: To assess the response rates to BCG in the different tumor stages, to describe the clinical impact of transurethral resection of the prostate (TURP) before BCG treatment, and to review the side effects of BCG treatment for PUC. METHODS: A systematic search was conducted using the PubMed database to identify original studies between 1977 and 2019 reporting on PUC and BCG. RESULTS: Of a total of 865 studies, ten were considered for evidence synthesis. An indication for BCG treatment was found in non-stromal invasive stages (Tis pu, Tis pd) and in stromal infiltrating cases (T1) of primary and secondary PUC when transitional cell carcinoma was the histology of origin. Studies including patients treated with TURP before BCG showed a better local response in the prostatic urethra with a higher disease free survival (DFS) (80-100% vs. 63-89%) and progression free survival (PFS) (90-100% vs. 75-94%) than patients in studies in which no TURP was performed. However, this difference in recurrence and progression in the prostate neither affected the total PFS (57-75% vs. 58-93%), nor the disease specific survival (70-100% vs. 66-100%). CONCLUSIONS: The use of resection loop biopsies of the prostatic urethra in appropriate cases during the primary work-up for suspected PUC, as well as the use of the current TNM classification for PUC, need to be improved. BCG therapy for non-stromal invasive stages of PUC show a good local response. Local response is further improved by a TURP before BCG therapy, although the overall prognosis does not seem to be affected. Further evidence for BCG treatment in the rare cases of stromal invasive PUC is needed. Specific side effects of BCG treatment for PUC are not reported.