Presentation Authors: Shigehisa Kubota*, Tetsuya Yoshida, Susumu Kageyama, Otsu, Japan, Taichi Sano, Ritto, Japan, Takashi Osafune, Uji, Japan, Yuji Sakano, Higashi-Ohmi, Japan, Chul Jang Kim, Kohka, Japan, Akihiro Kawauchi, Otsu, Japan
Introduction: Pirarubicin (THP) has a high affinity for bladder tumor cells and a short reaction time, thus, short-duration instillation chemotherapy may have a recurrence-preventive effect. No previous study has compared the treatment efficacy of short indwelling time of THP with standard treatments. We evaluated the prophylactic effect of a single short-duration instillation of THP immediately after TURBT for low-risk non-muscle-invasive bladder cancer (NMIBC) compared with that of a standard 60-minute instillation of mitomycin C (MMC).
Methods: We retrospectively studied the clinical profiles and outcomes of 111 patients with low risk NMIBC who underwent TURBT between 2006-2016. THP (30mg/30ml) was administered into the bladder immediately after TURBT for 15 minutes, or MMC (20mg/20ml) was administrated for 60 minutes; TURBT alone was performed in the control group. We compared the recurrence-free survivals between groups by the Kaplan-Meier method and Cox regression models.
Results: Of the 111 patients, 30 were included in the THP group, 23 in the MMC group, and 58 in the control group. The median follow-up period was 27.0 months. The recurrence-free survival (RFS) rates at 1 year and 3 years, respectively, were 89.3% and 85.4% in the THP group, 95.7% and 85.2% in the MMC group, and 73.4% and 59.7% in the control group (p=0.011, Fig.). A multivariable Cox regression analysis showed that the instillation of THP and MMC were independently associated with a significant improvement of RFS (Table).
Conclusions: A single short-duration instillation of THP for 15 minutes immediately after TURBT significantly prevented intravesical recurrence in low-risk NMIBC patients, and its effect was similar to that of MMC instillation for 60 minutes. This method can be expected to reduce the risk of extravesical leakage of anticancer agents due to hyperextension of the bladder.