Role of temporary iridium-192 interstitial implant in the treatment of carcinoma of the prostate

Abstract

Two hundred patients with biopsy proven adenocarcinoma of prostate with Stages A to C were treated between July 1977 and December 1985. All patients underwent bilateral retroperitonea 1 pelvic lymph node dissection for staging and transperineal afterloading Iridium-192 implant to prostate; delivering minimum tumor dose of 30 to 40 Gy over 40-60 hours. In addition, all patients with Stage B and C disease also received external megavoltage radiation to prostate to doses of 30 to 40 Gy over 34 to 44 weeks. Local tumor control was defined by digital examination only when there was complete resolution of previously palpable nodules, masses or induration. This was achieved in 191/200 (95.5%) patients with minimum followup of 4 years (median 6.8 years). 74 patients had been rebiopsied at an average time interval of 2 years after completion of treatment. Only 12 (16%) patients had positive biopsies. The overall 5 year actuarial survival of entire group is 95%. Disease free survival has been correlated with stage and histology. Treatment related moderate to severe complications such as cystitis, proctitis, rectal ulcerations or fistulae occurred in 14% of patients initially (in first 100 cases). This has been critically analyzed in detail and several modifications and corrections have been introduced in the original treatment protocol resulting in complication rate of less than 4% without significant change in overall local tumor control.