CHICAGO, IL—For the approximately 60,000 men in the United States with prostate cancer who are asymptomatic after radical primary treatment yet have a prostate-specific antigen (PSA) relapse, it’s safe to postpone androgen deprivation therapy (ADT), an observational study presented at the 2014 American Society of Clinical Oncology (ASCO) Annual Meeting concluded.
“Our analysis suggests that patients undergoing immediate ADT initiation at PSA-only relapse have a similar survival to those who defer ADT initiation when they have a clinical progression or two or more years after the PSA-only relapse,” said Xabier Garcia-Albeniz, MD, Department of Epidemiology, Harvard School of Public Health, Boston, MA.
“Rising PSA levels trigger a lot of anxiety, and many men want to start treatment as soon as possible,” said Dr. Garcia-Albeniz. “These findings suggest that there may be no need to rush to ADT. If our results are confirmed in randomized trials, patients could feel more comfortable waiting until they develop symptoms or signs of cancer that are seen on a scan, before initiating ADT.”
Waiting also reduces and/or delays the cost of treatment as well as side effects that can significantly reduce quality of life, such as sexual dysfunction, osteoporosis and risk of bone fracture, hot flashes, cognitive decline, fatigue, loss of muscle mass, increased cholesterol, weight gain, and depression, all of which may become more severe the longer a patient stays on therapy.
Currently, no guidelines exist for timing of ADT initiation in this population. ASCO guidelines state, “the critical issue is to determine whether there is benefit and how large it is for starting ADT while patients are asymptomatic,” while the National Comprehensive Cancer Network acknowledges a “therapeutic dilemma regarding the role of ADT,” he said. Another challenge: each patient has a unique evolution of the disease; therefore, PSA and clinical events are used to personalize treatment initiation.
The study followed 2,012 men using data from CaPSURE (Cancer of the Prostate Strategic Urologic Research Endeavor), a longitudinal observational prospective registry of more than 14,300 men with biopsy-proven prostate cancer, funded and coordinated by the Department of Urology at the University of California, San Francisco. These patients in CaPSURE are treated and followed in usual practice settings. Started in 1995, 43 study sites have enrolled patients nationwide.