Use of postsurgical radiotherapy for prostate cancer declining despite evidence of benefit
Despite strong evidence and guidelines supporting its use, postsurgical radiation therapy for prostate cancer at risk of recurrence is declining in the United States. The study, published online in the journal European Urology (doi:10.1016/j.eururo.2015.04.003), finds fewer than 10% of patients at risk of prostate cancer recurrence received postoperative radiotherapy within 6 months of surgery in the United States.
Although radical prostatectomy (RP) is a common curative treatment for localized prostate cancer, approximately 30% of patients will develop biochemical recurrence after surgery, meaning their prostate-specific antigen (PSA) level will again rise. In cases of more aggressive cancers, biochemical recurrence (also called biochemical failure) may occur in as many as 60% to 70% of patients.
Three large, randomized, prospective clinical trials, two conducted in Europe and one in the United States, have demonstrated that postoperative radiotherapy (RT) in patients with adverse pathological features reduces risk of PSA recurrence, may prevent the need for androgen deprivation therapy (ADT), and may reduce metastasis and improve survival.
In the United States, the American Society for Radiation Oncology (ASTRO) and American Urological Association (AUA) recommend offering adjuvant RT to patients with adverse pathologic features found at the time of surgery.
To investigate how available evidences were being implemented, researchers from the American Cancer Society and Massachusetts General Hospital led by Helmneh Sineshaw, MD, MPH, of the American Cancer Society analyzed data from the National Cancer Data Base (NCDB), a national hospital-based cancer registry database that captures data on approximately 70% of newly diagnosed cancer cases in the United States. The study included 97,270 patients, ages 18 to 79 years, whose diagnoses were made between 2005 and 2011.
The data showed that receipt of RT after RP decreased steadily between 2005 and 2011, from 9.1% to 7.3%. Although RT use was higher in younger patients and in those at highest risk for recurrence, overall rates of utilization remain low, with fewer than 20% of patients in subgroups most likely to benefit from receiving RT.
The authors said declining utilization of RT could be due to multiple factors including patient preference, physician and referral bias, concern for toxicity, lack of a consistent survival benefit seen in the updated randomized trials, or a growing preference for salvage radiation, done if a patient's PSA rises in the weeks and months after surgery.
Nonetheless, the authors said additional effort is needed to ensure patients are counseled regarding their options and available evidence.
"The declining trend in the utilization of postoperative RT calls for the attention of clinicians to make appropriate referrals to radiation oncologists or clinical oncologists when appropriate," they wrote.