To prospectively evaluate the outcome of combined microwave-induced bladder wall hyperthermia and intravesical mitomycin C instillation (thermochemotherapy) in patients with recurrent non-muscle-invasive bladder cancer.
Between 2003 and 2009, 21 patients (median age 70 years, range 35-95 years) with recurrent non-muscle-invasive bladder cancer (pTaG1-2 n = 9; pTaG3 n = 3; pT1 n = 9; concurrent pTis n = 8) were prospectively enrolled. Of 21 patients, 15 (71%) had received previous intravesical instillations with bacillus Calmette-Guérin, mitomycin C and/or farmorubicin. Thermochemotherapy using the Synergo system was carried out in 11 of 21 patients (52%) with curative intent, and in 10 of 21 patients (48%) as prophylaxis against recurrence.
The median number of thermochemotherapy cycles per patient was six (range 1-12). Adverse effects were frequent and severe: urinary urgency/frequency in 11 of 21 patients (52%), pain in eight of 21 patients (38%) and gross hematuria in five of 21 patients (24%). In eight of 21 patients (38%), thermochemotherapy had to be abandoned because of the severity of the adverse effects (pain in 3/8, severe bladder spasms in 2/8, allergic reaction in 2/8, urethral perforation in 1/8). Overall, six of 21 patients (29%) remained free of tumor after a median follow up of 50 months (range 1-120), six of 21 patients (29%) had to undergo cystectomy because of multifocal recurrences or cancer progression and seven of 21 patients (33%) died (2/7 of metastatic disease, 5/7 of non-cancer related causes).
Given the high rate of severe side-effects leading to treatment discontinuation, as well as the limited tumor response, thermochemotherapy should be offered only in highly selected cases of recurrent non-muscle-invasive bladder cancer.