The absorption of pirarubicin instilled intravesically immediately after transurethral resection of superficial bladder cancer

OBJECTIVES: To assess the validity of the prophylactic use of pirarubicin ([2'R]-4-O-tetrahydropyranyl-doxorubicin) immediately after transurethral resection of bladder tumour (TURBT), using pharmacodynamic studies. PATIENTS AND METHODS: The study included 20 consecutive patients with superficial bladder cancer. Pirarubicin (30 mg/50 mL or 30 mg/100 mL, 10 patients each) was instilled immediately after TURBT and retained in the bladder for 1 h. Blood samples were obtained before and at 15, 30, 60 and 120 min after the instillation. After retaining the drug for 1 h all the intravesical fluid was collected and assayed for pirarubicin. RESULTS: The plasma pirarubicin concentration in those receiving either dose was below detectable levels at any time after instillation. The mean recovery rate of pirarubicin in the drained fluid was 73%. CONCLUSION: The intravesical instillation of pirarubicin immediately after TURBT caused no detectable plasma concentration and few systemic side-effects.