Stereotactic body radiation therapy (SBRT) for the treatment of prostate cancer is less costly than the standard intensity-modulated radiation therapy (IMRT), but the higher doses of radiation delivered by SBRT can increase genitourinary toxicity.
The retrospective study yielding this finding centered on a national sample of Medicare beneficiaries aged 66 years and older who underwent IMRT or SBRT as a primary treatment for prostate cancer (PCa) from 2008 to 2011. A newer technique than IMRT, SBRT delivers a greater dose of radiation so that the entire course can be completed in 1-2 weeks rather than the 7-9 weeks required for IMRT.
James B. Yu, MD, of the Department of Therapeutic Radiology at Yale University School of Medicine, New Haven Conn., and colleagues matched 1,335 patients undergoing SBRT to 2,670 men undergoing IMRT with similar follow-up (six months, 12 months, or 24 months).
The mean treatment cost was approximately one-third lower for SBRT ($13,645) than for IMRT ($21,023), but more men undergoing SBRT experienced genitourinary (GU) toxicity at 6 months after treatment initiation (15.6% of SBRT patients vs 12.6% of IMRT patients), the investigators reported online ahead of print in the Journal of Clinical Oncology. At 24 months after treatment initiation, 43.9% of the SBRT group and 36.3% of the IMRT group had GU toxicity, including urethritis, urinary incontinence, and/or obstruction.
Dr. Yu’s team did note that even when including the cost of treatment for these complications, overall SBRT-related costs were still lower than the cost of IMRT. The investigators noted that their data are not definitive, and prospective correlation with randomized trials is needed.