THERMAL INTRAVESICAL CHEMOTHERAPY IN ADJUVANT TREATMENT OF HIGH RISK NON-MUSCLE INVASIVE BLADDER CANCER

OBJECTIVES: To evaluate the oncological results of hyperthermic Mitomycin C (MMC) in adjuvant treatment of high-risk non-muscle invasive bladder cancer and to assess its side-effect profile. METHODS: Patients who were followed up in two reference university hospitals due to high-risk non-muscle invasive bladder tumors were included in the study. High-risk patients according to the EAU non-muscle invasive bladder cancer guideline, patients who were rejected early cystectomy, patients who could not be treated with BCG due to a shortage, and patients for whom the cystectomy would be too risky due to their comorbidities were included in the study. All patients were followed up for at least 24 months with physical examination, cystos- copy, and urine cytology at 3-month intervals. Transurethral tumor resection was performed in all patients and a non-muscle invasive urothelial carcinoma was diagnosed pathologically. Hyperthermic MMC was administered with Synergo system SB-TS 101. Records were kept prospectively and evaluated retrospectively. RESULTS: Fifty-eight high-risk group patients 18 (31%) of whom were at pTa stage and 40 (69%) at pT1 stage were included in the study. During a mean follow-up of 42 months, 34 (58%) patients had recurrence, while 5 (8%) patients progressed to muscle-invasive disease. Eleven (19%) of the patients underwent radical cystectomy. The mean time to relapse was 10 months (3-34 months), and the mean time to progression was 41 months (6-87 months). Five-year overall survival, cancer-specific survival, progression-free survival, and relapse-free survival of the patients were 76%, 88%, 90% and 38%, respectively. Multifocality alone was found to be an independent risk factor (HR: 0.26; 95% Cl: 0.08-0.78; p=0.016) affecting recurrence. The observed side effects included tachycardia, cystitis, dysuria, macrohematuria, procedure-related pain, and allergic skin reactions. Treatment had to be discontinued in one patient due to a diffuse skin reaction. CONCLUSIONS: Thermal intravesical MMC therapy is a safe treatment and it could be effective treatment option in preventing disease progression in patients with high risk and non-muscle invasive bladder cancer with unsuccessful Bacillus Calmette-Guerin (BCG) or who could not be treated with BCG for other reasons.