Feasibility and patient tolerance of a novel transrectal ultrasound hyperthermia system for treatment of prostate cancer

This report describes patient tolerance and toxicity of a transrectal ultrasound hyperthermia system used with external beam radiation therapy in treatment of locally advanced prostate cancer. Nine patients with clinical T2B-T3B (4th edition AJCC criteria) disease received external beam radiation therapy, with two hyperthermia treatments scheduled at least 1 week apart during the first 4 weeks of radiation. Five patients also received hormonal therapy. Interstitial and anterior rectal wall thermometry were performed. Median temperature for each treatment (T50) was 40.8°C and mean CEM T90 = 43°C was 3.4 min. Rectal wall temperature was maintained at ≤40°C. Treatment duration was limited in three of 17 sessions due to positional discomfort which was alleviated with light IV sedation and use of a `New Life' mattress (Comfortex, Inc. Winoba, MN, USA). Acute toxicity was limited to NCI common toxicity criteria grade 1 and no excess toxicity was noted with full course radiation therapy +/− hormonal therapy. The...