Long-term urinary function after transperineal brachytherapy for patients with large prostate glands

Purpose: To summarize longer-term postbrachytherapy morbidity in patients w ith prostate glands >50 cm(3). Methods and Materials: From 1997 to 1998, 33 patients with a transrectal ul trasound-based prostate volume >50 cm(3) were treated at the University of Washington by I-125 (144 Gy) or Pd-103 (115 Gy) implantation for prostate c arcinoma. These 33 patients comprised 7% of the total implant patient popul ation. Twelve patients were treated with neoadjuvant androgen ablation befo re implantation. The I-125 source strength ranged from 0.34 to 0.5 mCi and the Pd-103 source strength ranged from 1.1 to 1.4 mCi (pre-NIST-99). The to tal number of sources implanted was 94-223 (median 155). Despite the typica l implant-related volume increase, the postimplant CT-defined prostate volu mes were generally well-covered by the prescription isodose (median coverag e 92%, range 80-100%). The preimplant urinary obstructive symptoms were qua ntified by the criteria of the American Urological Association. Results: Of the 33 patients, 12 developed acute postimplant urinary retenti on, all presenting within 24 h of Implantation. Patients who developed post implant retention lasting >1 week were generally treated with intermittent self-catheterization. By 1 month, 85% of patients were catheter free. By 1 year, only 1 patient (4%) remained in urinary retention; the remainder of c ases had resolved spontaneously. With follow-up of 1.7-2.6 years, the last American Urological Association scores were higher than the pretreatment sc ores in 15 patients and lower in 7 patients. No patient developed permanent urinary incontinence. Long-term changes in the American Urological Associa tion scores were unrelated to whether the patient had been in urinary reten tion after implantation. Two patients developed rectal fistulas; they had p reimplant transrectal ultrasound prostate volumes of 53 and 59 cm(3), in th e low range for this group of patients. No other patient had persistent rec tal bleeding suggestive of clinically significant proctitis. The pretreatme nt serum prostate-specific antigen level was 3.3-15 ng/mL (median 7.2) and the last serum prostate-specific antigen level 0.1-1.6 ng/mL (median 0.2). Conclusion: Patients with larger prostate volumes appear to have moderate m orbidity and a satisfactory technical outcome with brachytherapy. We do not believe the occurrence of two severe rectal complications was related to t he prostate volume per se. Our experience and that of others calls into que stion the validity of using prostate volume as a criterion for patient suit ability for prostate brachytherapy. (C) 2001 Elsevier Science Inc.