Radiation Therapy and Prostate Cancer

Radiation Therapy Most Common Treatment for Prostate Cancer

Radiation therapy is the most common treatment for prostate cancer regardless of cancer stage, prostate-specific antigen (PSA) level, and prognosis and risk rating, according to a study published online by JAMA Oncology.

Prostate cancer remains the most commonly diagnosed solid organ tumor among U.S. men with an estimated 233,000 new cases and 29,480 deaths in 2014. Earlier diagnosis and treatment advances have meant increased use of aggressive local treatments, particularly radical prostatectomy and radiation therapy, which can result in adverse effects. Patients must often consider the recommendations of physicians, the aggressiveness of their cancer, whether active surveillance is preferred over treatment, and health care costs, according to the study background.

Jim C. Hu, M.D., M.P.H., formerly of the David Geffen School of Medicine at UCLA, Los Angeles, and now of the Weill Cornell Medical College, New York, and coauthors examined predictors for treatment and use of watchful waiting or active surveillance (monitoring of the disease with the expectation to begin treatment if the cancer progresses) for indolent (less aggressive) prostate cancer. The research was conducted at UCLA and authors analyzed Surveillance, Epidemiology and End Results (SEER)-Medicare linked data for a total of 37,621 men diagnosed with prostate cancer from 2004 to 2007.

The authors found radiation therapy (57.9 percent) was the most common treatment followed by radical prostatectomy (19.1 percent) and other treatments including watchful waiting or active surveillance (9.6 percent, WW-AS). Patient demographics and tumor characteristics account for 40 percent of patients undergoing prostatectomy, 12 percent choosing “watchful waiting” or active surveillance, and 3 percent undergoing radiotherapy, according to the results.

While radiation treatment was the most common treatment (48 percent – 66 percent) regardless of stage, PSA level, and prognosis and tumor rating, radical prostatectomy was influenced by PSA level. WW-AS was guided by clinical stage, as well as prognosis and tumor rating, while androgen-deprivation therapy (ADT) was influenced by cancer stage, PSA level and prognosis and risk rating.

The authors also found WW-AS increased with advanced age and a consultation with a medical oncologist also increased use of WW-AS. Asian men and married men were associated with the least likely use of WW-AS. Increased radiation use was found among men with advancing age, more significant co-existing illnesses and tumor characteristics, and it was most likely used when men were referred to a radiation oncologist, according to the results.

“There remains an increased use of treatments in men diagnosed as having prostate cancer and underuse of active surveillance in men with low-risk disease. There is an increased use of radiotherapy among all risk groups and in particular patients with indolent disease with limited correlation according to tumor biological characteristics and patient health. Further research into identifying determinants that drive decision-making recommendations for patients diagnosed with low-risk prostate cancer are needed. These findings must be balanced when considering health care reform initiatives to improve quality of care,” the study concludes.

In a related commentary2, Charles L. Bennett, M.D., Ph.D., of the Medical University of South Carolina, Charleston, and coauthors write: “We welcome additional reports regarding patterns of care in the recent era, where there likely remain significant patterns of underutilization of some treatments and overutilization of other treatments. Moreover, continued identification of predictors for treatment decision by clinicians and patients is critical, particularly when optimizing efficacy, safety and value.”

“Recent studies have identified nonclinical factors, including self-referral by urologists to investor-owned facilities that provide intensity-modified radiation therapy, and concerns that these treatments may represent overutilization of expensive treatments and may also adversely affect patient safety when administered to patients who do not need these treatments. Comparative effectiveness studies are essential, as the patterns of care studies often leave us with more questions than answers,” the authors conclude.

1. JAMA Oncol. Published online February 19, 2015. doi:10.1001/jamaoncol.2014.192.
2. JAMA Oncol. Published online February 19, 2015. doi:10.1001/jamaoncol.2014.183.