Urinary morbidity and incontinence following transurethral resection of the prostate after brachytherapy

Purpose: We analyzed the risk of urinary morbidity and incontinence in patients undergoing transurethral resection of the prostate (TURP) following prostate brachytherapy. Materials and Methods: A total of 2,050 patients underwent transperineal radioactive seed implantation of the prostate with or without external beam radiation therapy for the diagnosis of prostate cancer between June 1990 and February 2004. Of the 2,050 patients 38 (2%) underwent minimal (channel) TURP due to urinary symptoms or retention. Urinary morbidity was recorded prior to implantation and at followup intervals using the International Prostate Symptom Score and quality of life assessment scores. All patients underwent post-implantation computerized tomography based dosimetry at 1 month. The dose to 90% of prostate volume, prostate volume covered by 15% of the prescription dose and dose to 30% or 5 cm(2) of urethral volume were recorded. Of the 38 patients 11 (29%) underwent Pd-103 implantation alone and 12 (32%) received a partial (67%) Pd-103 implant with external beam radiation therapy to a median dose of 45 Gy (range 41.4 to 59.4), while 15 (39%) underwent I-125 implantation alone. Median followup after implantation was 38 months (range 2 to 97). Results: Seven of the 38 patients (18%) undergoing TURP had urinary incontinence. Median time to TURP was 11 months (range 1 to 73). 25% Of patients who received an implant and external beam radiotherapy had urinary incontinence following TURP compared with 15% who underwent implantation alone (p = 0.26). There was no significant correlation between incontinence risk based on the dose to 90% of prostate volume (p = 0.32), the dose to 30% or 5 cm(2) Of urethral volume (p = 0.30) or prostate volume covered by 15% of the prescription dose (p = 0.36). Two of 24 patients (8%) who had underwent 2 years or less after implantation had urinary incontinence compared with 5 of 14 (36%) who underwent TURP greater than 2 years following implantation (p = 0.04). Conclusions: Urinary incontinence developed in 18% of patients who underwent TURP following prostate brachytherapy. No significant correlations between radiation dose, preimplant prostate volume or hormonal therapy were identified with regard to this risk. Patients in late retention or with obstructive symptoms (greater than 2 years) following implantation who require TURP are at greater risk for incontinence.