Intravesical Bacillus Calmette-Guerin Therapy for Superficial Bladder Cancer: Effect of Bacillus Calmette-Guerin Viability on Treatment Results

Abstract

Forty patients with superficial bladder cancer were treated via intravesical BCG for prophylaxis against tumor recurrence, residual carcinoma or flat carcinoma in situ. A single course of intravesical BCG therapy was successful in 6 of 11 patients (55%) treated for residual carcinoma and 6 of 12 (50%) treated for carcinoma in situ. Of 17 patients receiving a single course of BCG for prophylaxis 11 remained free of tumor during short-term followup. A 2nd course of therapy was administered to failures in each treatment category, which resulted in favorable responses in 5 of 6 patients treated for prophylaxis, 2 of 5 treated for residual tumor and 3 of 6 treated for carcinoma in situ. Over-all complete responses were achived in 16 of 17 patients (94%) treated for prophylaxis, 8 of 11 (73%) for residual carcinoma and 8 of 12 (66%) for carcinoma in situ, with a mean followup from the final treatment of 9.3, 12.3 and 7.9 mo. respectively. Favorable results occurred more frequently among patients who exhibited a granulomatous inflammatory response in the bladder and delayed hypersensitivity skin test response to purified protein derivative. Marked variability in viability of BCG organisms was observed among different lots of BCG and a direct relationship was observed between BCG vaccine viability and therapeutic efficacy. Most patients who failed initial therapy with a low viability lot of BCG responded favorably to re-treatment with a higher viability lot. The results suggest that the level of viability of each lot of BCG vaccine should be verified before clinical use.