Active Surveillance Safe Primary Management Strategy for Patients With Low-Grade Prostate Cancer

Peter Carroll, MD

Active surveillance (AS) is an emerging primary management strategy for men with lower-risk, localized prostate cancer. At intermediate follow-up (median, 52 months), investigators from the University of California at San Francisco (UCSF) AS program found that treatment can safely be delayed in patients who are carefully selected but then demonstrate disease progression after a period of AS. Five-year prostate-cancer-specific survival was 100% and overall survival was 98%.

Allison Glass, MD, and Peter Carroll, MD, presented these data on behalf of their co-investigators at the 2012 Society of Urologic Oncology annual meeting, in Bethesda, Maryland.

For the analysis, 691 of 1000 men who are currently in the UCSF AS program provided consent for the analysis. Two-thirds of the men in the cohort met the institution’s strict AS criteria, which included: ≤T2, PSA <10 ng/mL, Gleason score ≤6 without pattern 4 or 5, ≤ 33% diagnostic biopsy cores cancer-positive, and ≤50% single core with cancer involvement.

Clinical risk at diagnosis was defined using the UCSF Cancer of the Prostate Risk Assessment (CAPRA) score, and surveillance monitoring conformed to the UCSF AS Protocol (Table).

Table. UCSF Active Surveillance Protocol

PSA and DRE

Every 3 to 4 months

Prostate ultrasound

Every 6 to 12 months

Prostate biopsy

Every 1 to 2 years

DRE indicates digital rectal exam; PSA, prostate-specific antigen; UCSF, University of California, San Francisco.

Ninety-three percent of enrolled patients were Caucasian, with a mean age of 62.2 ±7.9 years. Two-thirds had T1 disease. At baseline, 84% had a low (0-2) CAPRA risk score; 15% had an intermediate (3-5) score.

Of the 81% (563) of patients who underwent one or more repeat biopsies, 37% (206) had an increase in Gleason score, and 22% (123) had increased volume in more than 33% of positive cores. Thirty-six percent of the cohort underwent delayed intervention. For this group, treatment-free survival at 5 years was 62%. Twentytwo percent underwent radical prostatectomy (RP); 10% received radiotherapy, and 4% were prescribed androgen-deprivation therapy. Gleason upgrade was found to be the strongest predictor of delayed RP (hazard ratio = 3.8; 95% CI, 2.8-5.1; P <.01).

Allison Glass, MD

A Shift in the Field

The rate of delayed treatment in this study cohort, according to the investigators, is similar to that of other institutions, and is most often precipitated by grade migration.As a primary management strategy for men with lower-risk prostate cancer, Glass indicated that AS represents a “significant shift in the field.” A growing consensus supports its use for men with low-risk prostate cancer. But its adoption is significantly lagging behind medical opinion. “It is estimated that only about 10% of men who are candidates will choose active surveillance in this country,” said Glass. In Europe this figure is about 30%— higher, but still behind the evidence.

Younger men especially choose to undergo radical intervention, potentially enduring treatment-related effects that can severely impact quality of life. Many of these men will never have symptoms of the disease or die. The authors noted that they did not see any worse outcomes in the men in the original cohort who did not meet the strict UCSF criteria for AS. Men who had delayed surgery experienced similar rates of adverse pathologic findings and biochemical recurrence compared with those who underwent immediate surgery.

“The big message from our data is that, at an intermediate follow-up (52 months), active surveillance appears to be a safe primary management strategy for men with lower-risk disease,” the authors concluded.