Minneapolis VA Health Care System
The Prostate Cancer Debate
A Department of Veterans Affairs clinical trial that spanned nearly 20 years finds that surgery does not significantly reduce all-cause or prostate cancer deaths for men who are diagnosed in the early stages of the disease.
The landmark study, known as the Prostate Cancer Intervention Versus Observation Trial, or PIVOT, was published July 13, 2017, in the New England Journal of Medicine. It was funded by the VA Cooperative Studies Program, which conducts large clinical and epidemiological studies. The National Cancer Institute and the Agency for Healthcare Research and Quality provided extra funding.
Dr. Timothy Wilt, a physician-researcher with the Center for Chronic Disease Outcomes Research at the Minneapolis VA Health Care System and a professor of medicine at the University of Minnesota, led the trial.
The researchers conclude there was no “statistically significant difference” in deaths from any cause or specifically prostate cancer, when comparing early surgery and observation. The latter involves regular monitoring using the PSA (prostate specific antigen) blood test and delayed treatments to reduce symptoms if they develop.
Death from prostate cancer in men treated with observation was uncommon (about 11 percent of men) and rare (about 5 percent) in men with low-risk disease. The researchers also say that while most men with localized prostate have an excellent prognosis without early treatment men with more aggressive tumors have a poorer prognosis.
Some of the findings seem to suggest that some mortality results leaned more favorably toward surgery than observation. But Wilt cautions that those findings were small in absolute terms (6 percent or less), not “statistically significant,” and should be weighed against large increases in early, bothersome, long-lasting and sometimes serious treatment harms. For example, surgery caused complications within 30 days in about 20 percent of men and resulted in long-term increases of 30 percent or more in urinary incontinence, erectile dysfunction, and dissatisfaction with sexual performance as well as treatment related bother and reductions in daily functioning. Surgery decreased disease progression treatment by about 25 percent though most treatment was for asymptomatic or PSA reasons where treatment benefits are not clear
“These results suggest that for most men, observation or PSA-based active monitoring can result in similar very long-term all-cause and prostate cancer-specific mortality, while avoiding harms of radical intervention,” Wilt says. “Findings from PIVOT and similar studies will improve prostate cancer care, in part, by reducing over-diagnosis and overtreatment harms, as well as by stimulating new research to identify safe and effective therapies in men with higher-risk disease.”
“The medical and lay community is recognizing the importance of observation, or PSA-based active monitoring rather than early radical intervention with surgery or radiation, for many men with PSA-detected early-stage prostate cancer in reducing treatment harms while preserving length of life and avoiding prostate cancer death” Wilt says. “More needs to be done to increase observation and reduce overtreatment with surgery or radiation, especially in men with low PSA and low risk disease while also identifying safe and effective treatments for men with higher risk disease.”