A 3-arm randomized control trial to compare the efficacy of re-circulant hyperthermic intravesical chemotherapy versus conventional intravesical mitomycin C and BCG therapy for intermediate-risk non-muscle invasive bladder cancer.

Introduction: To evaluate the efficacy and side effects of re-circulant hyperthermic intravesical chemotherapy versus conventional treatments for intermediate risk non-muscle invasive bladder cancer (NMIBC).

Methods: A randomized 3-arm, parallel group trial was conducted at a single tertiary care centre. 135 patients with low-grade intermediate-risk cancer, having undergone complete resection of bladder tumor were included. Patients were assigned 1:1:1, to receive intra-vesical chemo-hyperthermia (C-HT), mitomycin-C (MMC) or BCG therapy. There was no treatment crossover. Patients were followed up with check cystoscopy every 3 months for histopathological recurrence.

Results: The three arms were comparable in terms of age, gender, tumor size, number of tumors and clinical stage or grade of tumors. Mean tumor size was 2.58 (± 0.88) cm and the mean number of tumors resected was 2.04 (± 1.02) (Range 1-5). There was no significant difference between the various groups for tumor recurrence (χ2 = 1.96, p = 0.375) or time to recurrence (13.6 vs. 10.8 vs. 9.8 months, p = 0.844) though incidence of non-healing necrotic area was higher with C-HT (22.2% vs. 11.1% and 4.8%, χ2 = 6.093, p = 0.048). Median (IQR) follow up period was 26 (12-52) months. Treatment discontinuation or drug intolerance was significantly higher in BCG arm (p = 0.03).

Conclusions: Intravesical C-HT with MMC, conventional MMC and BCG are equally effective and comparable alternatives for intravesical therapy in low-grade intermediate-risk NMIBC. Higher incidence of non-healing resection site with C-HT and higher local symptoms with BCG are a concern.