New findings from Rutgers Cancer Institute of New Jersey indicate survival benefit lacking for older patients given hormone treatment as a sole therapy

Research from investigators at Rutgers Cancer Institute of New Jersey shows a popular prostate cancer treatment that disables male hormones known to promote growth of prostate cancer lacks survival benefit for older men with localized disease.

The study focuses on this specific treatment (also known as ADT), which for the past 15 years has become a popular alternative to surgery, radiation or conservative management when used as the only therapy. The work appears in the July 14, 2014, edition of JAMA Internal Medicine.

Grace Lu-Yao
Grace Lu-Yao
Photo: Kim Sokoloff

The research utilized information from 66,717 Medicare patients aged 66 and older diagnosed with clinical stage T1-T2 prostate cancer (cancer that did not spread beyond the prostate) between 1992 and 2009.  These men did not have surgery or radiation treatment within six months of their diagnosis. The data were compiled from the population-based Surveillance, Epidemiology, and End Results (SEER) database linked to Medicare files.

Grace Lu-Yao, a cancer epidemiologist at the Cancer Institute of New Jersey and professor of medicine at Rutgers Robert Wood Johnson Medical School, is the lead author. Previous research on ADT by her team with similarly aged men only followed patients until 2003.  In this study, investigators extended the follow-up period by six years and included an additional 47,000 patients from different population areas covered by the SEER database. Median follow-up for overall survival was nine years.

In this new study, investigators found that when ADT was administered as the primary treatment for localized disease during the initial six month period following diagnosis, the hormone therapy was not associated with improved 15 year overall survival or prostate cancer-specific survival, especially among the majority of older men in the study group.  This was compared to those patients who received no treatment of any type and instead underwent regular assessment – a strategy known as ‘conservative management.’

The study also showed little difference in survival rates between patient populations in areas of the country where ADT was more frequently used as a sole treatment versus areas where it was not.  In both high- and low-use areas where ADT was used as the sole treatment, 15-year prostate cancer-specific survival was measured at 90.6 percent among patients with moderately differentiated cancer.

Lu-Yao notes that while previous research has shown ADT is appropriate for use in high-risk patients and in combination with other treatments, sole use – especially in an older population – should be carefully considered. “Because of the potential side effects of osteoporosis, diabetes and decreased muscle tone, clinicians must carefully consider the rationale behind ADT treatment if used as the primary therapy for older patients,” she says. Since  the data only included men 66 and older, results could differ for younger men.

Along with Lu-Yao, the author team consists of Peter C. Albertsen, University of Connecticut Health Center; Dirk F. Moore, Weichung Shih, and Yong Lin, all Cancer Institute and Rutgers School of Public Health; and Robert S. DiPaola and Siu-Long Yao, both Cancer Institute and Rutgers Robert Wood Johnson Medical School. The study, Fifteen-Year Survival Outcomes Following Primary Androgen Deprivation Therapy for Localized Prostate Cancer, was supported by a grant from the National Cancer Institute (R01 CA116399) and in part through the Cancer Institute core grant (NCI CA-72720-10).