Dysuria Following Stereotactic Body Radiation Therapy for Prostate Cancer

Abstract

Dysuria following prostate radiation therapy is a common toxicity that adversely affects patients QOL and may be difficult to manage. This study sought to evaluate the incidence and severity of dysuria following stereotactic body radiation therapy (SBRT) for prostate cancer, testing the hypothesis that SBRT treatment has comparable rates of dysuria to those of IMRT and/or brachytherapy. 204 patients treated with SBRT monotherapy from 2007 to 2010 at a single institution for localized prostate carcinoma with a minimum follow up of three years were included in this retrospective review of data that was prospectively collected. All patients were treated to 35-36.25Gy in 5 fractions delivered with robotic radiosurgery with real time fiducial tracking. Dysuria and urinary function were assessed via Question 4b (Pain or burning on urination) of the Expanded Prostate Index Composite (EPIC)-26 and the American Urological Association (AUA) Symptom Score at baseline and at 1, 3, 6, 12, 18, and 24, 30 and 36 months. Medication utilization was documented at each visit. 204 patients (82 low-, 105 intermediate-, and 17 high risk according to the D’Amico classification) at a median age of 69 years (range 48-91) received SBRT monotherapy for their localized prostate cancer, having a median follow up of 47 months. Bother associated with dysuria significantly increased from a baseline of 12% to a maximum of 43% at one month (p<0.0001), improving to 21% at 3 months. However, only 18% of all patients felt that pain or burning on urination was a moderate to big problem. Of those patients, 92% reported return to baseline within a median time of 3 months. There were two distinct peaks of moderate to severe dysuria bother at 1 month and at 6-12 months, with 9% of patients experiencing a late transient dysuria symptom flare. While a low level of dysuria was seen through the first two years of follow-up, it returned to below baseline by three years. The median baseline AUA score of 7.5 significantly increased to 11 at 1 month (p<0.0001) and returned to 7 at 3 months (p = 0.54). Patients with dysuria had a statistically higher AUA score at baseline and at all follow-ups up to 30 months. 28 % of patients utilized alpha-agonists prior to treatment, which increased to 55% at 1 month before returning to baseline at 2 years post-SBRT. The rate and severity of dysuria following SBRT is comparable to patients treated with other radiation modalities. Dysuria correlates with other urinary symptoms. Conservative management, including alpha-agonist utilization, may help minimize the bother associated with dysuria.