A VA–led 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 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 blood test and delayed surgery to reduce symptoms if they develop.

In addition, they say, surgery to remove the prostate resulted in immediate and long–term harms that were common, bothersome, and sometimes serious. These included early surgical complications such as bleeding, blood clots, and infections; long–term urinary, erectile, and sexual dysfunction; and a negative impact on how well men performed their daily activities. Surgery did reduce disease progression and the need for subsequent procedures, although most treatment was for asymptomatic and PSA progression, for which benefits are not certain. In other words, it is unclear what men with no symptoms stand to gain from surgery, even if they've been diagnosed with prostate cancer and have experienced a sharp rise in PSA levels.

The landmark study, known as the Prostate Cancer Intervention Versus Observation Trial, or PIVOT, was published on July 13, 2017, in the New England Journal of Medicine.

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.

"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."

At the same time, Wilt acknowledges that observation is rarely practiced in the United States, despite what he says is evidence that it is effective and reduces negative after–effects. "This is likely based on widespread beliefs and fears that a cancer diagnosis may elicit among men, their families, and physicians, rather than scientific evaluation of benefits, harms, and costs," he says. "That needs to improve. We hope the PIVOT study will help with that."

The latest findings in the PIVOT trial were consistent with earlier results that had been published at the 12–year mark of the study. The trial involved 731 men with localized prostate cancer and took place at 44 VA sites and eight non–VA academic medical centers. The men were split about evenly into two groups and were randomly assigned to surgery, also known as radical prostatectomy, which is surgical removal of the walnut–sized prostate, or to the "observation" group that was monitored with PSA tests.

A few 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) and not "statistically significant," according to the researchers' statistical methods. The findings should also be weighed against large increases in early, bothersome, long–lasting, and sometimes serious harms from surgery, he says.