ANAHEIM, CaliforniaA new paradigm of prostate cancer treatment is emerging that includes active surveillance with delayed treatment even for younger men with low-risk disease, Marc A. Dall'Era, MD, said at the American Urological Association 102nd Annual Scientific Meeting (abstract 611).
"Screening is finding prostate cancers earlier, and in younger men. The question is, if we watch these cancers, can we find the ones that will progress and still cure them if we delay intervention," said Dr. Dall'Era, of the Department of Urology, University of California, San Francisco.
Dr. Dall'Era and his colleagues reviewed the clinical profiles and disease characteristics upon entry and over time of 478 men with low-risk prostate cancer managed initially with active surveillance (mean age, 63; mean PSA, 6.5 ng/mL). The researchers had complete data for 320 men. Low-risk disease was defined as PSA less than 10 ng/mL, Gleason sum 6 or less (no pattern 4/5), stage T1 or T2, or 33% or less positive cores (50% or less any single core positive): 71% of patients met all of these criteria.
Most of these low-risk patients (87%) had a PSA level of 10 ng/mL or less, 64% were stage T1, 92% had a Gleason score less than 7, and 83% had 33% or less positive cores on biopsy samples. None of the patients moved to active treatment sooner than 6 months after diagnosis.
To track progression, PSA was measured every 3 months, transrectal ultrasound (TRUS) was performed every 6 to 12 months, and repeat prostate needle biopsy was done at 12- to 24-month intervals. Progression was defined as PSA velocity greater than 0.75 ng/mL/yr, a rise in Gleason score, or greater than 50% increase in lesion size on TRUS.
The investigators found that 28% of patients progressed by at least one of the criteria: 25% had PSA velocity greater than 0.75 ng/mL/yr, 14% had PSA velocity greater than 2 ng/mL/yr, and 8% had a PSA doubling time less than 2 years; 33% had an increase in Gleason score, and 7% had an increase of greater than 50% in lesion size. "We found no baseline characteristic that identified men who would have progression vs no progression," Dr. Dall'Era said.
The researchers reported that 21% of patients received secondary treatment, at a median of 2 years after diagnosis (range, 1 to 14 years). Rise in Gleason score was the only significant marker for switching to active treatment (P < .01). Dr. Dall'Era noted that only 71% of those receiving treatment had evidence of clinical progression.