Single Short Retention Instillation of Pirarubicin Prevents Intravesical Recurrence of Low-risk Non Muscle Invasive Bladder Cancer

This study evaluated the efficacy of a single instillation of pirarubicin with a short retention time for preventing intravesical recurrence of low-risk non-muscle-invasive bladder cancer. We analyzed 165 patients with low-risk non-muscle-invasive bladder cancer who underwent transurethral surgery. Single instillation of pirarubicin with 15-min retention time immediate after surgery was performed in 47 (28%) patients. The other patients (118, 72%) were treated without instillation therapy. The primary endpoint was recurrence-free survival. Median overall follow-up was 50 (range=6-134) months. Recurrence-free survival at 1 and 5 years was 91% and 72%, and 79% and 54% in the group treated with pirarubicin, and that treated with surgery alone, respectively (p=0.031). Cox's hazard analysis revealed lack of instillation and larger tumor size (>10 mm) as significant factors for risk of recurrence. No adverse events regarding intravesical chemotherapy were observed. Pirarubicin instillation with 15-min retention time can prevent intravesical recurrence of low-risk bladder tumors.