Active surveillance and intermediate-risk prostate cancer
Posted Dec 11 2010 12:00am
A Reuters report on a forthcoming study in the Journal of Clinical Oncology has suggested that some men with intermediate-risk prostate cancer may be able to safely defer treatment in favor of monitoring the disease over time (through active surveillance) for a period of at least 4 years.
The Reuters report addresses a paper by Cooperberg et al. The paper is based on a series of 466 prostate cancer patients who have been managed with active surveillance at the University of California, San Francisco (UCSF).
According to Dr. Cooper, in the USA today, between 25 and 40 percent of all newly diagnosed prostate cancer patients have localized disease that falls into the intermediate-risk category. The wide range is a consequence of the fact that there are varying definitions of “intermediate risk.” However, it has been clear for a while that active surveillance held potential as a management starategy for at least some of these men.
Of the 466 patients managed at UCSF, 90 were categorized as having intermediate-risk disease and the other 376 had low-risk disease. After their initial diagnosis, they received PSA tests and digital rectal exams about every 3 months, ultrasound tests every 6 to 12 months, and follow-up biopsies every 1 to 2 years.
At a median follow-up of 4 years, Cooperberg et al. report that:
55/90 intermediate-risk patients (61 percent) and 203/376 low-risk patients (54 percent) demonstrated no growth in their tumors.
The difference in results between the low- and intermediate-risk groups of patients was not statistically significant.
Compared to the patients with low-risk tumors, those with intermediate-risk tumors
113/376 low-risk patients (30 percent) and 32/90 of the intermediate-risk patients (35 percent) had opted to initiate treatment after some time on active surveillance.
Of the patients who had opted to initiate treatment by surgery (which was the most common form of therapy)
Dr. Peter Carroll, the chairman of the Department of Urology at UCSF, and a highly regarded authority on the management of early stage prostate cancer, has apparently “stressed that active surveillance would be an option only for carefully selected men with intermediate-risk cancer” in an e-mail to Reuters, stating that, “Such patients require careful evaluation and an assessment can be made only on the basis of a very well performed biopsy and by experienced clinicians.”
As one might expect, good candidates for active surveillance among patients with intermediate-risk, localized prostate cancer include men with a limited life expectancy (based not only on their chronological age but also on their overall health status and and specific comorbidities such as chronic cardiac conditions). However, according to Reuters, Dr. Carroll has also indicated that “the take-home message for men with prostate cancer is that they should not ‘rush’ into treatment, but seek opinions about all of their options, including active surveillance.”
The “New” Cancer InfoLink has long believed that active surveillance would be shown to be an appropriate management strategy for at least some men initially diagnosed with intermediate-risk prostate cancer, e.g.,
Men with a PSA < 10 ng/ml and Gleason 3 + 4 disease (as opposed to Gleason 4 + 3 disease) and a life expectancy of < 15 years.
Men with a PSA only slightly greater than 10 ng/ml and a Gleason score of 6 and a life expectancy of < 15 years.
Clearly we will need more data over time to see if we can clarify the opportunity that active surveillance offers for patients initially diagnosed with intermediate-risk disease, but this study does appear to significantly expand the pool of patients for whom active surveillance is a potentially reasonable management option.