(HealthDay News) — Rates of observation as management for low-risk prostate cancer vary widely, and androgen-deprivation therapy (ADT) is not associated with improved survival for men with localized prostate cancer, according to two studies published online July 14 in JAMA Internal Medicine.
Karen E. Hoffman, M.D., M.P.H., from the University of Texas MD Anderson Cancer Center in Houston, and colleagues examined the impact of physicians on the management of low-risk prostate cancer. The study included 2,145 urologists who diagnosed low-risk prostate cancer in 12,068 men. Of these, 80.1 percent received treatment and 19.9 percent were observed. The researchers found that the case-adjusted rate of observation varied from 4.5 to 62.4 percent of patients across urologists and from 2.2 to 46.8 percent across consulting radiation oncologists. The diagnosing urologist accounted for 16.1 percent of the variation in terms of up-front treatment versus observation, while 7.9 percent of variation was due to patient and tumor characteristics.
Grace L. Lu-Yao, M.P.H., Ph.D., from Rutgers Robert Wood Johnson Medical School in New Brunswick, N.J., and colleagues conducted a population-based cohort study involving 66,717 Medicare patients to examined the long-term survival impact of primary ADT in older men with localized prostate cancer. During a median follow-up of 110 months, the researchers found that primary ADT was not associated with improved 15-year overall or prostate cancer-specific survival.
“Primary ADT should be used only to palliate symptoms of disease or prevent imminent symptoms associated with disease progression,” Lu-Yao and colleagues write.
One author from the Hoffman study disclosed financial ties to Varian Medical Systems. Several authors from the Lu-Yao study disclosed financial ties to the pharmaceutical industry.