Active surveillance is a viable option for many men with low-risk disease, but more research is needed to determine the critical points at which active treatment should be recommended. Researchers presented two new studies on active surveillance (or “watchful waiting”) during the 105th Annual Scientific Meeting of the American Urological Association (AUA) in San Francisco. A special press conference was held on June 1, 2010.. The press conference was moderated by prostate cancer expert J. Brantley Thrasher, MD, of the University of Kansas Medical Center.

Recent controversy has linked prostate cancer testing with overtreatment. However, not all prostate cancers require active treatment. During active surveillance, a patient is monitored regularly for signs of prostate cancer progression with regular prostate-specific antigen (PSA) tests and digital rectal exams. Urologists monitor key factors for evidence of progression, such as PSA velocity (rate of change over time) and PSA doubling time, or disease progression on surveillance biopsy to determine if active treatment is necessary. At present, there is no universal standard for these triggers.

Using data from a prospective phase II study of patients with lower-risk (T1b-T2b, N0M0, Gleason 7 or lower, PSA less than 15 ng/ml) disease, researchers in Canada calculated the proportion and frequency of patients who would have been offered active treatment (based on commonly used triggers) to assess whether this would lead to unacceptably high rates of treatment. Of the original 453 patients following the active surveillance protocol, 305 continue to be monitored. The percentage of patients who might have been treated based on threshold, doubling time and velocity were 42 percent, 50 percent and 84 percent, respectively.

The second study, from researchers in San Francisco, explores the safety and efficacy of active surveillance using a cohort of 477 men (mean age 62 at diagnosis) most of whom had low-risk disease (74 percent). Two-hundred ninety-six men had at least one repeat biopsy, with 125 experiencing grade progression. To date, 153 men have undergone active treatment for their disease. Of the 75 men who underwent radical prostatectomy, 33 percent had a Gleason score less than 6, 68 percent had stage T2 or lower disease and 85 percent had negative surgical margins. 25 percent had extracapular extension and 7 percent had seminal vesicle invasion. There have been no cases of biochemical recurrence in this group.

“Overdetection should not be used synonymously with overtreatment when it comes to prostate cancer,” Dr. Thrasher said. “These two studies alone show just how valuable active surveillance protocols can be when disease is managed well and treatment is recommended appropriately.”

Source
American Urological Association