Patient selection for hemiablative focal therapy of prostate cancer: variables predictive of tumor unilaterality based upon radical prostatectomy.

BACKGROUND: The application of focal therapy for low-risk prostate cancer (PCa) depended on appropriate patient selection. No definitive criteria existed to characterize patients who may potentially benefit from an organ-sparing approach. We evaluated pretreatment clinical parameters that may predict unilateral PCa amenable to hemigland thermoablation.
METHODS: In total, 538 patients with complete data from the Duke Prostate Center (DPC) Outcomes database with low- to low-intermediate-risk PCa (prostate-specific antigen<10 ng/mL, biopsy Gleason score < or =7, and clinical stage T1c-T2b) treated with radical prostatectomy (RP) were included in the dataset. Patients underwent diagnostic prostate biopsy (PBx) at Duke or community hospitals from 1996 to 2006. Clinical and biopsy parameters were assessed as to the ability to predict PCa unilaterality verified by RP pathology.
RESULTS: The strongest predictor of pathologic unilaterality was PBx unilaterality. The sensitivity and specificity for biopsy unilaterality to predict pathologic unilaterality was 88.4% and 34%, with a positive predictive value of 28% and a negative predictive value of 91%. PBx unilaterality (odds ratio [OR] = 3.88; 95% confidence interval [CI], 2.14-7.05; P < .0005) and negative family history of PCa (OR = 1.83; 95% CI, 1.09-3.05; P = .21) was associated with a higher probability of unilateral disease by multivariate regression.
CONCLUSIONS: Two pretreatment clinical variables were significantly predictive of unilateral PCa: negative family history of PCa and PBx unilaterality. These variables may be used to select men with low- to low-moderate-risk PCa for hemiablation. Further work is necessary to decrease the false-negative and false-positive rates associated with PBx to improve predictability for PCa laterality.