Bacillus Calmette-Guerin. Is monthly maintenance an option for transitional cell carcinoma of the bladder?

Purpose: Recently, a Southwest Oncology Group study (SWOG 8507) demonstrated increased efficacy for a bacillus Calmette-Guerin (BCG) maintenance (mtce) program (3 weekly treatments at 3 months, 6 months, and every 6 months thereafter for 3 years) following 6 weekly instillations with BCG as compared to no mtce ("6+3" protocol). The remarkable results from the mtce arm were unfortunately accompanied by grade 3 or 4 toxicity in 26%. In fact; only 16% of the patients in the maintenance arm received BCG at each of the 7 prescribed courses. Herein, we report on a series of 37 patients with high risk (rapidly recurring grade 2 or 3) Ta, T1 transitional cell carcinoma (TCC) or carcinoma in situ (TIS) of the bladder who received 6 weekly BCG treatments followed by monthly mtce for one year. Patients and Methods: This was a prospective, non-randomized trial of 37 patients with high risk superficial transitional cell carcinoma (TCC) who received one or two 6-week induction courses of intravesical Tice BCG, followed by monthly mtce for 12 months. Entry criteria were identical to those of SWOG 8507. The mean follow-up interval was 40.7 months. Results: Twenty eight of thirty-seven patients (75.7%) remained free of disease recurrence at a median of 40.7 (range 13-101) months. Only one patient progressed to muscle invasive disease. Only 1 of 37 (2.7%) patient experienced grade 3/4 toxicity. Conclusion: In this single institution, monthly maintenance protocol, freedom from recurrence was significant with dramatically less grade 3 or 4 toxicity than reported in SWOG 8507.