Impact of bacillus Calmette–Guérin therapy of upper urinary tract carcinoma in situ: comparison of oncological outcomes with radical nephroureterectomy

The clinical benefits of bacillus Calmette–Guérin (BCG) therapy for the management of upper urinary tract carcinoma in situ (CIS) remain unclear. We aimed to compare the efficacy and safety of BCG therapy for upper urinary tract CIS with those of radical nephroureterectomy (RNU). Of 490 patients with upper urinary tract carcinoma, we retrospectively reviewed the post-treatment course of 58 patients with upper urinary tract CIS who underwent either RNU (RNU group) or BCG therapy (BCG group). Efficacy and safety were compared between the RNU and BCG groups. Inverse probability treatment-weighted (IPTW)-adjusted multivariate Cox regression analysis was performed to identify the influence of BCG therapy on prognosis. The RNU and BCG groups included 20 and 38 patients, respectively. No significant difference was found in patients’ background, including age, sex, and performance status, between the groups. The reason underlying the selection of BCG therapy was bilateral CIS of the upper urinary tract (50%), solitary kidney (26%), unwillingness to undergo RNU (13%), and ineligibility for surgery (11%). The cytology became negative in 30 (79%) out of 38 patients after a 6-week course of BCG therapy, and 17 (57%) out of 30 patients remained negative. BCG-related adverse events (AEs) were observed in 92% of patients. The most common AE was cystitis (76%), followed by fever (50%). No significant differences were found in the progression-free, cancer-specific, and overall survivals between the RNU and BCG groups. IPTW-adjusted multivariate analysis revealed that BCG therapy did not worsen the prognosis of these patients. The limitations of our study were its retrospective design and small sample size. In conclusion, BCG therapy for upper urinary tract CIS might be a useful alternative for patient ineligible for RNU under careful observation for AEs.