MP55-08: High Intensity Focused Ultrasound and Cryoablation Focal Therapy for Intermediate Risk Prostate Cancer: Oncologic and Functional Outcomes

Masatomo Kaneko*, Alireza Ghoreifi, Los Angeles, CA, Samuel Peretsman, Charlotte, NC, Dordaneh Sugano, Giovanni Cacciamani, Amir Lebastchi, Suzanne Palmer, Manju Aron, Los Angeles, CA, Osamu Ukimura, Kyoto, Japan, Inderbir Gill, Andre Abreu, Los Angeles, CA

Introduction: To evaluate oncologic and functional outcomes following High Intensity Focused Ultrasound (HIFU) and Cryoablation (CRYO) focal therapy (FT) for localized prostate cancer (PCa).

Methods: We identified consecutive patients who underwent hemi-gland HIFU (h-HIFU) or hemi-gland CRYO (h-CRYO) FT as primary treatment for D’Amico intermediate risk PCa (IRB# HS-17-00749). Patients were selected by 12-core systematic and target biopsy and had unilateral index lesion. Follow up biopsy (FU-PBx) was performed from 6-12M and every 2Y thereafter. Primary endpoint was Treatment Failure (TF) defined as radical (any whole-gland) treatment, systemic therapy, metastases, or PCa-specific mortality. Secondary endpoints were survival-free from i) biochemical failure (BF, PSA nadir + 2ng/mL); ii) Grade Group (GG)=2 on FU-PBx, iii) repeat FT, iv) radical treatment, and v) systemic therapy. Kaplan-Meier method was used for survival evaluation. International Prostate Symptom Score (IPSS), International Index of Erectile Function (IIEF-5) and continence (zero pad) were also evaluated. Statistically significant if p<0.05.

Results: 184 patients met inclusion criteria: 121 (66%) h-CRYO and 63 (34%) h-HIFU. The baseline characteristics were comparable among h-HIFU vs h-CRYO, respectively, as follows: median age (65 vs 67 Y, p =0.15), PSA (5.9 vs 6.7ng/mL, p = 0.081), PSA density (0.18 vs 0.17ng/mL2, p = 0.61), number of positive cores (3 vs 3, p=0.14) and maximum PCa core % (50% vs 50%, p = 0.59). h-CRYO had higher rate of GG3, as follows: GG1 (2% vs 7%), GG2 (79% vs 50%) and GG3 (19% vs 42%); p < 0.001. The median follow up was longer for h-CRYO (30M) vs h-HIFU (24M); p=0.005. PSA nadir was 1.1ng/mL for h-HIFU vs 0.91ng/mL for h-CRYO, p=0.53. The 3-year TF-free survival was: 88% for h-HIFU and 95% for h-CRYO, p=0.32. The 3-year free survival was, for h-HIFU vs h-CRYO, respectively: BF (80% vs 70%, p=0.89); GG=2 on FU-PBx (63% vs 90%, p<0.001), repeat FT (93% vs 98%, p=0.40), radical treatment (87% vs 99%, p=0.04) and systemic therapy (100% vs 96%, p=0.23). One patient on h-CRYO developed bone metastases, but no patient died. Median difference from pre- to post-FT IPSS (0 vs 1.5; p=0.99) and IIEF-5 (0 vs 2; p=0.14) were similar for h-HIFU vs h-CRYO, respectively. Continence was maintained in 100% h-HIFU vs 98% h-CRYO, p=1.00.

Conclusions: Hemi-gland HIFU or CRYO for intermediate risk PCa provide acceptable short-medium term oncologic outcomes with excellent function outcomes. Hemi-gland CRYO provided longer radical treatment-free survival than hemi-gland HIFU.

Source of Funding: None.