NEW YORK (Reuters Health) - Carefully selected men with “low-risk” prostate cancer can safely delay treatment and opt instead for active surveillance, researchers report in the April issue of The Journal of Urology.

With active surveillance, or “watchful waiting,” patients with early prostate tumors are monitored regularly and only treated if their cancer progresses.

“Active surveillance with delayed treatment, if necessary, for select patients appears to be safe” and associated with a low risk of the cancer spreading, the researchers conclude.

Despite the potential survival advantages associated with prostate cancer treatment, senior investigator Dr. Bertrand Guillonneau told Reuters Health, “there is still a large number of patients who are over-treated and who will suffer from prolonged side effects that impair their quality of life.”

“Active surveillance, based on strict criteria,” added Guillonneau, “might be a way to sort out patients with growing tumor that requires treatment from quiescent tumor that will not progress.”

To study the safety of active monitoring instead of immediate treatment of men with low-risk prostate cancer, Guillonneau, of Memorial Sloan-Kettering Cancer Center, New York, and colleagues studied 268 men younger than age 75 years.

All of the men had been given multiple treatment options but ultimately chose active surveillance over immediate treatment. The men had early “low-risk” disease, based on their prostate specific antigen (PSA) level and initial biopsy findings.

The men had a second “restaging” biopsy immediately before active surveillance began and no treatment in the following 6 months. They subsequently underwent physical exams and PSA tests every six months with biopsies recommended every 1 to 2 years.

Of that initial pool of men electing active surveillance of their cancer, 43 eventually chose treatment or had evidence of cancer progression prompting recommendation of treatment by their physician. Following delayed treatment (radiation or surgery,) all but one were cured of their cancer. The remaining 219 patients remained on active surveillance without evidence that their disease had spread.

At 2 years the probability of staying on active surveillance was 91 percent. At 5 years, it was 75 percent.

“Our study indicates that 75 percent of the patients who are real candidates for active surveillance will still fulfill the same criteria 5 years later, demonstrating the absence of noticeable (disease) progression,” Guillonneau said.

“These patients should still be closely monitored,” he concluded, “but it seems likely, for many of them, the prostate cancer will not ultimately develop and will not require any kind of active and therefore morbid treatment.”

SOURCE: The Journal of Urology, April 2009.