VAIL, CO USA (UroToday.com) - Background: Stereotactic body radiation therapy (SBRT) delivers high daily doses of radiation to the prostate while minimizing radiation to adjacent normal tissues.
Large fraction sizes may increase the risk of post-treatment functional decrements. This study reports on patient reported outcomes following SBRT for clinically localized prostate cancer.
Methods: Between February, 2008 and December, 2010, 175 hormone-naïve patients with clinically localized prostate cancer were treated with 35-36.25 Gy SBRT delivered using the CyberKnife Radiosurgical System (Accuray) in 5 fractions. Quality of life was assessed before and after treatment using the Expanded Prostate Cancer Index Composite (EPIC)-26.
Results: 175 patients (72 low-, 93 intermediate- and 10 high-risk) at a median age of 69 years (range, 48-90 years) received SBRT with a minimum follow-up of 36 months. The EPIC urinary summary scores declined transiently at 1 month (mean change, -7.5) and experienced a second, more protracted decline between 6 months and 18 months (mean change from baseline at 12 months, -4.4) before returning to near baseline at two years post-SBRT. The EPIC bowel summary scores declined transiently at 1 month (mean change, -9.9) before returning to near baseline at two years post-SBRT. The EPIC sexual summary scores showed a gradual progressive decline over the 2 years following SBRT (mean change, -9.8) without recovery. The EPIC hormonal summary scores did not illustrate a statistically significant difference three years post-treatment.
Conclusions: In the first three years following SBRT, the impact of treatment on urination and defecation were minimal. Of note, a transient late mild decrease in urinary function was observed. However, urinary and bowel function recovered to near baseline by 2 years post-SBRT. Sexual dysfunction steadily increased during the first 2 years following treatment. SBRT for clinically localized prostate cancer was well tolerated with treatment related functional decrements comparable to conventionally fractionated radiation therapy or brachytherapy.
Presented by Joy S. Kim; Leonard N. Chen, MD, PhD; Thomas P. Kole, MD, PhD; Rudy Moures; Thomas Yung; Siyuan Lei; Brian T. Collins, MD; Simeng Suy, PhD; Anatoly Dritschilo, MD; John H. Lynch, MD; and Sean P. Collins, MD, PHD at the 24th International Prostate Cancer Update - February 19 - 22, 2014 - Cascade Conference Center - Vail, Colorado USA
Department of Radiation Medicine, Georgetown University Hospital, Washington, DC 20007, U.S.A.
Department of Urology, Georgetown University Hospital, Washington, DC 20007, U.S.A.
L. Chen and J. Kim contributed equally to this work