Hyperthermia in the treatment of bladder tumours

10-year single-center experience of combined intravesical chemohyperthermia for nonmuscle invasive bladder cancer

Aim: Owing to the limited efficacy and significant toxicity of most topical intravesical agents for the management of nonmuscle invasive bladder cancer (NMIBC), a search for new therapeutic modalities continues. This study evaluates the safety and efficacy of a relatively new modality, combined intravesical chemotherapy and hyperthermia, using the intravesical chemohyperthermia system. Methods: The data summarize our 10 years of experience in the Department of Urology at Bnai Zion Medical Center, Israel. Ninety two patients with NMIBC (88 evaluable) were treated according to the adjuvant (66 patients) and the neoadjuvant (26 patients) protocols, with up to 7 years follow-up. Results: Over the follow-up period, 56 out of 64 patients (72%) treated according to the adjuvant protocol remained free from recurrences. The progression rate was 4.7% (three out of 64 patients). An initial complete response was documented in 19 out of 24 patients (79%) treated according to the neoadjuvant protocol. During the follow-up period, 16 out of these 19 patients (84%) remained free from recurrences. All of the recurrences in this group had stage Ta grade 1 tumors. Conclusion: Microwave-induced chemohyperthermia is a safe and effective treatment option for patients with NMIBC, both in the adjuvant and neoadjuvant settings. The use of this treatment modality did not expose the patients to an increased risk of progression.

Multicentric study comparing intravesical chemotherapy alone and with local microwave hyperthermia for prophylaxis of recurrence of superficial transitional cell carcinoma

PURPOSE

To compare the efficacy and local toxicity of the intravesical instillation of a cytostatic drug versus the same cytostatic agent in combination with local hyperthermia as an adjuvant treatment, after complete transurethral resection (TURB) of superficial transitional cell carcinoma (TCC) of the bladder.

PATIENTS AND METHODS

The study was designed as a prospective, multicentric, randomized trial. Eighty-three patients suffering from primary or recurrent superficial (Ta-T1) TCC of the bladder, after a complete TURB, were randomly assigned to receive intravesical instillations of mitomycin C (MMC) alone, for 41 patients, and MMC in combination with local microwave-induced hyperthermia, for 42 patients. For the combined approach, a new system, Synergo101-1 (Medical Enterprises, Amsterdam, the Netherlands) was used. The effectiveness evaluation end points of the study were evaluation of recurrence-free survival and the estimated probability of recurrence. The safety evaluation end points included subjective and objective side effects and clinical complications. For the efficacy end point, Kaplan-Meier analysis was employed, with the log-rank test for significance. Minimum follow-up time was 24 months.

RESULTS

Of the 83 randomly assigned patients, 75 completed the study according to the protocol and had valid cystoscopy results. Survival analysis of the 75 assessable patients demonstrated a highly significant difference in the survival curves in favor of thermochemotherapy. Subjective intolerance and clinical complications were significantly higher but transient and moderate in the combined treatment group.

CONCLUSION

In our series, endovesical thermochemotherapy appears to be more effective than standard endovesical chemotherapy as an adjuvant treatment for superficial bladder tumors at 24-month follow-up, despite an increased but acceptable local toxicity.

Combination of intravesical chemotherapy and hyperthermia for the treatment of superficial bladder cancer: preliminary clinical experience

The prevalence of superficial transitional cell carcinoma of the bladder (STCCB) is still increasing in spite of improved adjuvant chemotherapeutic and/or immunoprophylaxis approaches. Thus, there is certainly an urgent need to improve our ability to control this disease. Local hyperthermia has a therapeutical potential for the treatment of many solid tumors, especially when used in combination with other treatments, such as radiation and chemotherapy. In particular, a synergistic or, at least, supra-additive anti-tumor cell killing effect was documented when local hyperthermia was administered in combination with selected cytostatic drugs. Recently, advances in miniaturized technology have allowed the development of a system specifically designed for delivering an endovesical thermo-chemotherapy regimen in humans. In preliminary clinical experiences, insofar mainly carried out as mono-institutional investigations, the combined treatment using this system was demonstrated to be feasible, minimally invasive and safe when performed on out-patient basis. Moreover, the anti-tumoral efficacy seemed to be significantly enhanced when compared with that obtained using intravesical chemotherapy alone for both adjuvant (prophylaxis) and neo-adjuvant (ablative) approaches to superficial bladder cancer.

Pre-cystectomy intra-arterial cis-diamminedichloroplatinum II with local bladder hyperthermia for bladder cancer

A total of 6 patients with bulky pelvic bladder cancer underwent combination cis-diamminedichloroplatinum II (cisplatin) hypogastric artery infusion and local bladder hyperthermia as a preoperative adjunct to radical cystectomy. Pathological examination showed extensive tumor necrosis on the luminal side, with a gradient of tumor destruction to viable tumor on the serosal surface in 4 of the 6 bladders, while 2 specimens showed no tumor. Uninvolved portions of the bladders showed minor changes in the urothelium, submucosal edema and no effect on detrusor muscle or perivesical fat. Analysis of tissue for platinum revealed uptake by the tumors and normal tissues. Systemic effects of spillover cisplatin were not seen. Adjunctive preoperative hypogastric artery infusion of cisplatin is safe and well tolerated. Further study is required to determine the upper limits of safety of the regimen.

Pathologic effects of pre-cystectomy therapy with combination intra-arterial doxorubicin hydrochloride and local bladder hyperthermia for bladder cancer

Nine patients with bulky pelvic bladder cancer underwent combination doxorubicin hydrochloride hypogastric artery infusion and local bladder hyperthermia as a preoperative adjunct to radical cystectomy in a phase I study. Pathologic examination of the cystectomy specimens showed extensive tumor necrosis on the bladder luminal side, with a gradient of tumor destruction to viable tumor on the bladder serosal surface in 8 of the 9 bladders. Normal portions of the bladder showed minor changes in the urothelium, marked submucosal edema and hyperemia, and viable detrusor muscle. One bladder showed no viable tumor and fibrosis of the entire bladder wall. Adjunctive preoperative hypogastric artery infusion of doxorubicin hydrochloride/bladder hyperthermia is safe, well tolerated and merits further study to determine the upper limits of safety of doxorubicin hydrochloride and hyperthermia temperature.

Photoluminescent thermometer probes: temperature measurements in microwave fields

Based on luminescence, the photoluminescent thermometer can in principle function in electromagnetic field coupling and perturbation. Several prototypal probes that have been constructed and tested demonstrate the feasibility of the concept. Temperature resolution of approximately 0.3 degrees C has thus far been achieved. The probes are needle-shaped, sturdy and less than 1 millimeter in size. This thermometer system has excellent potential application in monitoring and controlling tissue temperatures when microwaves are used to induce hyperthermia for cancer treatment.