Cryoablation for localized prostate cancer: Feasibility in large prostates

Prostate volume may influence the technical feasibility of focal therapy and increase failure rates. In this study, we aimed to characterize the outcomes of patients undergoing primary focal therapy with cryoablation, and evaluate the effectiveness of this approach in larger glands.

We retrospectively identified men who underwent focal therapy as primary treatment for localized prostate cancer at our institution. Treatment failure was defined as clinically significant prostate cancer on post-treatment biopsy (GG2-5) or need for subsequent therapy. Kaplan Meier survival curves were generated to compare event free survival between patients with large glands (defined as >60 grams) and small glands (<60 grams).

Seventy-two patients underwent primary focal therapy for localized prostate cancer, all with cryoablation, with a median follow up time of 21.2 months (IQR 6.8, 68.3). Gland size ranged from 17 to 177 grams. In total, 16 (22.2%) experienced treatment failure, at a median of 20 months (IQR 12, 30) after treatment. Of the 16 failures, 12 were biopsy-proven (4 in-field, 1 near-field, 7 out-of-field). Gland size was not associated with treatment failure or toxicity in this small cohort. Among 18 patients with prostate volume >60 grams, 5 (27.8%) failed. Failure free survival did not differ between large and small glands (P = 0.70). Only 1 complication occurred in the population (Clavien grade I hematuria managed with observation, prostate volume 59 grams).

Focal therapy with cryoablation is feasible among patients with larger gland size with low complication rates and no significant difference in treatment failure rates compared to men with smaller prostates in this small cohort.