MRI Fusion Cryoablation: Is There an Outcome Difference Between Anterior and Posterior Lesions?

Introduction: Cryotherapy pioneered ablation therapy for prostate cancer (PCa), initially using larger ablations. As the technique advanced, a more targeted approach was developed irrespective of lesion location. However, some clinical guidelines have addressed concerns for treating posterior areas. This study evaluates the validity of these concerns. Materials and Methods: We retrospectively studied 814 Magnetic Resonance Imaging Fusion Target Cryotherapy (MRFTC) treatment-naïve patients with PCa with a single index lesion (2013-2023) under local anesthesia. We grouped by treatment location: anterior, anterior-posterior, and posterior. Disease progression, defined as conversion to radical treatment, initiation of hormonal therapy, or development of metastases, was evaluated with survival analysis via the Kaplan-Meier log-rank test. Univariate and multivariable analyses were employed to compare outcomes among different treatment groups and other risk factors. Functional outcomes were evaluated using the Sexual Health Inventory for Men (SHIM) and International Prostate Symptom Score questionnaires, with comparisons made over time and by lesion location through t-tests. Complication rates were documented across the various treatment areas. Results: The distribution of patients' characteristics across treatment groups was similar. Procedure pain scores were similar irrespective of lesion location. Five years post-MRFTC, 87%, 89%, and 90% of patients treated for anterior, anterior-posterior, and posterior lesions, respectively, remained progression-free with no significant variation between groups (p = 0.22). For all groups, there were significant improvements in urinary function (baseline vs. 3 months). The posterior group showed a marginal, yet statistically significant negative difference in SHIM scores at 3 months. However, the score recovered by 1 year where no additional significant changes were noted. The most common complication was urinary retention and no cases of rectal fistula were reported. Conclusions: Our findings challenge clinical guidelines suggesting avoidance of focal cryoablation for posterior lesions. Using MRFTC, cryotherapy has proven to be safe and effective, regardless of lesion location.