Disease burden predicts for favorable post salvage cryoablation PSA

Objective: We wanted to identify prognostic factors for favorable biochemical outcome (prostate specific antigen [PSA] < 0.6 ng/mL) after salvage prostate cryoablation.

Methods: The charts from 58 salvage cryoablation patients treated at Cleveland Clinic from 2004 through July 2009 were reviewed. Patient age, race, PSA at diagnosis, Gleason score, risk category, prostate volume, clinical T stage, number of cores positive, percent of cores involved with disease, ratios of number of cores positive to total cores biopsied and number of cores positive to prostate gland volume, and initial PSA results were studied. Initial PSA levels measured at 6-12 weeks post treatment of < 0.6 ng/mL were used as the criterion for a favorable outcome based on previously published data.

Results: Thirty-one percent of patients had unfavorable postoperative PSA levels. The number of positive biopsy cores (P = .012), ratio of positive cores to prostate volume (mL) (P = .004), and, marginally, the percentage of cores positive divided by total number of cores biopsied (P = .060) were prognostic for favorable PSA outcomes. A higher ratio of number of cores positive to prostate volume (third quartile) had a lower (35%) chance of a favorable PSA than a lower ratio (first quartile) (OR = 0.35, 95% CI: .14-.84, P = .019).

Conclusion: Prostate gland disease burden as reflected by the number of cores positive and ratio of positive cores to gland volume (mL) is prognostic for favorable biochemical outcome after salvage whole-gland prostate cryoablation. Further study is warranted to better delineate this relationship.