Prognostic Indicators for Favorable nadir PSA (<0.4ng/ml) following Primary Whole Gland Prostate Cryoablation</h2>View PosterINTRODUCTIONWe previously identified nadir prostate specific antigen (PSA) less than 0.4 ng/ml as the best objective indicator of progression-free survival (PFS) after primary whole gland prostate cryoablation. Our aim is to identify preoperative prognostic variables for favourable nadir PSA (<0.4ng/ml).</p>METHODSThe charts from 2576 hormone naive men who underwent primary whole gland prostate cryoablation were included. Prognostic indicators including patient age, African American race, pretreatment PSA, Gleason sum, total prostate volume (TPV), clinical stage and PSA density (PSAD) results were reviewed. Post-cryoablation nadir PSA of <0.4ng/ml was used as the criterion for favorable outcome. Cox regression was used to assess predictors of favorable PSA nadir.</p>RESULTSMedian time that man reached nadir level was 3 months following surgery (IQR 1.6-6 months). A total of 1854 (79%) men had favorable postoperative nadir PSA (<0.4ng/ml) level. There were no significant associations of age, race, Gleason sum, TPV or clinical stage with nadir PSA (Table1). Lower pretreatment PSA level (RR.0.99, P<0.002) and lower PSAD (RR.0.75, P=0.01) were associated with favorable nadir PSA. We further stratified our cohort based on pretreatment PSA values<10 and ≥10 ng/ml and PSAD value <0.15 & ≥ 0.15. A 2 year Kaplan Meier analysis of favorable nadir outcome stratified by pretreatment PSA values revealed that the subsets of men with PSA < 10ng/ml (P < 0.001) and PSAD < 0.15 (P < 0.001) had significant favorable nadir outcomes (Figure 1).</p>CONCLUSIONIn men undergoing primary prostate cryoablation for localized prostate cancer, pretreatment PSA < 10ng/ml and PSAD <0.15 were associated with increased progression-free survival. These data suggest that earlier intervention will optimize treatment outcomes</p>Funding: none