(S043) Changes in Quality of Life After Radiation Therapy for Localized Prostate Cancer After Dissemination of Intensity-Modulated Radiation Therapy

Elyn H. Wang, Shiyi Wang, Pamela Soulos, Ronald Chen, Cary P. Gross, James B. Yu; Yale University School of Medicine; University of North Carolina School of Medicine

PURPOSE: Although intensity-modulated radiation therapy (IMRT) has replaced three-dimensional conformal radiotherapy (3D-CRT) to become the dominant form of external beam radiation therapy (EBRT) for prostate cancer, it is unclear whether this change in practice has been associated with improved patient outcomes. To estimate the impact of IMRT on health-related quality of life (HRQOL), we examined the HRQOL of elderly patients who had undergone EBRT during two eras: 1998–2001, when 3D-CRT was the standard of care for EBRT, and 2006–2009, when IMRT became the dominant form of EBRT.

METHODS: The Surveillance, Epidemiology, and End Results (SEER)-Medicare Health Outcomes Survey was used to obtain HRQOL measurements of Medicare beneficiaries who had received external beam radiotherapy for nonmetastatic prostate cancer and control subjects without cancer.

Control subjects during each era were matched 10:1 by use of propensity scores estimated from demographics and comorbid medical conditions. A total of 90 patients during the early era and 75 patients during the late era had eligible surveys both before and after treatment. Descriptive statistics and random effects linear regression were used to compare HRQOL between cancer patients and matched controls during the two eras. Area under the curve (AUC) was calculated to determine quality-adjusted life-years (QALYs) gained.

RESULTS: During the first 2 years after treatment, patients who were treated in the late era had 0.19 more QALYs compared with patients treated in the early era, relative to matched noncancer controls. Additionally, health utility and mental component scores at follow-up among cases during the early era declined significantly compared with controls, whereas they were similar between cases treated in the late era and their controls (P = .02 for difference in change in health utility and mental component scores between cases and controls during early vs late era).

CONCLUSIONS: External beam radiotherapy during an era after IMRT has become widespread is associated with improved HRQOL measures among prostate cancer patients compared with the era prior to IMRT dissemination.

Proceedings of the 97th Annual Meeting of the American Radium Society - americanradiumsociety.org