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Active surveillance with selective delayed intervention: walking the line between overtreatment for indolent disease and undertreatment for aggressive disease.

PURPOSE
To summarize the case for active surveillance for good risk prostate cancer with selective delayed intervention for rapid biochemical or grade progression, and review the results of a large phase II experience using this approach.


MATERIALS AND METHODS
A prospective phase II study of active surveillance with selective delayed intervention was initiated in 1995. Patients were managed initially with surveillance; those who had a PSA DT of 2 years or less, or grade progression on rebiopsy were offered radical intervention. The remainder were closely monitored.


RESULTS
The cohort consists of 299 patients with good risk prostate cancer, or intermediate risk prostate cancer in men over 70. The median PSA doubling time was 7.0 years. 35% had a PSA DT > 10 years. The majority of patients remain on surveillance. At 8 years, overall actuarial survival is 85%, and disease specific survival is 99%.


CONCLUSION
Most men with favorable risk prostate cancer will die of unrelated causes. The approach of active surveillance with selective delayed intervention based on PSA DT represents a practical compromise between radical therapy for all (which results in overtreatment for patients with indolent disease), and watchful waiting with palliative therapy only (which results in undertreatment for those with aggressive disease). The results at 8 years are favorable. Longer follow up will be required to confirm the safety of this approach in men with a long (>15 year) life expectancy.