Does the type of cryoprobe affect oncological and functional outcomes in men with clinically localized prostate cancer treated with primary whole gland prostate cryoablation?

Background:This study aimed to compare the oncological and functional outcomes of primary whole gland cryoablation of the prostate using the variable ice cryoprobe (V-Probe^®) and the conventional fixed-size ice probe.Materials and methods:We reviewed the Cryo On-Line Data Registry for men who were treated with primary whole gland prostate cryoablation from 2000 through 2017. A multivariate Cox proportional hazards model was used to compare timing to biochemical recurrence between the V-Probe^®and fixed-size ice probe after adjusting for preoperative prostate-specific antigen (PSA), neoadjuvant androgen deprivation therapy, preoperative Gleason score, and preoperative T stage.Results:A total of 1124 men were included. Median age, Gleason score, and pretreatment PSA were 70 years (interquartile range [IQR]: 65-74 years), 7 (IQR: 6-7) and 5.9 ng/mL (IQR: 4.6-8.1 ng/mL), respectively. The median follow-up time was 25.0 months (IQR: 11.2-48.6 months). V-Probes^®were used in 269 (23.9%) cases and fixed-size ice probes in 858 (76.1%) cases. After adjusting for clinical T stage, PSA, neoadjuvant androgen deprivation therapy and preoperative Gleason score, on the multivariate Cox regression model, we found that there was no significant difference between the type of probe and timing to biochemical recurrence (p = 0.35). On multivariate logistic regression, using the V-Probe^®was associated with a 91% increase in postoperative urinary retention compared to the fixed-size ice probe (p = 0.003).Conclusions:The use of the V-Probe^®versus conventional fixed-size ice probe was not associated with a difference in biochemical recurrence in patients undergoing primary cryoablation of the prostate.