Rectal complications associated with transperineal interstitial brachytherapy for prostate cancer

Purpose: As transperineal interstitial permanent prostate brachytherapy (TI PPB) grows in acceptance as an option in the treatment of organ-confined pr ostate cancer, its associated toxicities are being defined. This clinical r eport documents rectal toxicity from a large cohort of men treated by a sin gle practitioner for adenocarcinoma of the prostate. Methods and Materials: Eight hundred twenty-five men were treated from Sept ember 1992 to September 1998 with TIPPB. One hundred-forty were treated in conjunction with external beam irradiation (EBRT) and 685 with TIPPB alone. All patients were implanted under real-time ultrasound guidance. No dose-v olume histogram analysis was performed for this study. All patients were fo llowed at 5 weeks after the procedure, then every 3-6 months thereafter. Re ctal morbidity was graded by a modified RTOG toxicity scale. Therapy to con trol symptoms was recommended on an individual basis. Results: The median follow-up for the cohort is 48 months, A total of 77 pa tients (9.4%) reported Grade 1 toxicity at some time following an implant w hereas 54 patients (6.6%) reported Grade 2 toxicity. The peak post-TIPPB ti me for experiencing rectal toxicity was 8 months at which time Grade 1 and 2 rectal toxicity was reported in 9.5% of the patients. This improved over the subsequent months and resolved in all patients by 31/2 years. Four pati ents (0.5%) reported Grade 3 rectal toxicity with rectal ulceration identif ied on colonoscopy at 1 year from implant. Two of the four patients had col onic manipulation in the radiated portion of the colon which subsequently c aused it to bleed. None of the patients required blood product transfusion. In 3 of the 4 patients the Grade 3 rectal toxicity has resolved spontaneou sly and 1 patient continues to heal at the time of this report. No patient required hospitalization or surgical intervention. Conclusion: TIPPB is a tolerable and acceptable treatment option when used alone in early-stage, organ-confined adenocarcinoma of the prostate and in conjunction with EBRT in more advanced disease. This clinical report adds t o the growing literature regarding the potential morbidity associated with this procedure and indicates that serious rectal injury is rare. (C) 2000 E lsevier Science Inc.