Watchful waiting for localized prostate cancer in the PSA era: what have been the triggers for intervention?

objective• To report outcomes for patients with localized prostate cancer managed using a watchful waiting strategy at an American centre and to explore factors that have triggered intervention. PATIENTS AND

methods• From 1991 to 2005, 218 patients diagnosed with untreated localized prostate cancer were followed at Massachusetts General Hospital with prostate-specific antigen (PSA) monitoring and digital rectal examination (DRE). Re-biopsies were performed in 95 of the patients. • The median follow-up was 6.3 years. Clinical outcomes and features predicting intervention were examined.

results• At diagnosis, the median PSA level was 5.4 ng/mL. The Gleason score (GS) distribution was as follows: 95% with GS 6, 4% with GS 7, 1% with GS 8. The clinical T-stage distribution was as follows: 6% with T1a-b, 84% with T1c, 10% with T2. The median age was 71 years. • At 10 years, the overall survival was 79%, the cause-specific survival was 100%, the rate of distant metastasis was 5%, the rate of salvage androgen deprivation therapy was 15% and the rate of freedom from intervention (FFI) was 70%. • There was a PSA velocity of ≥ 2 ng/mL per year in 16% of patients, and a PSA doubling time of ≤ 3 years in 15% of patients. • Among the 95 re-biopsied men, the GS increased (grade progression) in 25% and the percentage of positive cores increased (volume progression) in 33%. • On multivariate analysis, only PSA doubling time and volume progression were independent predictors of FFI.

conclusions• In the present series, watchful waiting was associated with low rates of intervention and cancer progression. • As PSA doubling time and volume progression were the main triggers for intervention, these will be incorporated into the centre's current active surveillance protocol.