Water Vapor Ablation for Grade Group 3 Prostate Cancer

The goal of this study is to evaluate the safety and effectiveness of the Vanquish Water Vapor Ablation System ("Vanquish") in participants with Grade Group 3 (GG3) intermediate-risk prostate cancer. Participants will undergo therapy with the Vanquish System and complete follow up visits at 7 days, 6 weeks, 6 months, 12 months, 18 months, and 24 months.

Inclusion Criteria: * Participant has been diagnosed with Grade Group 3 (GG3) intermediate risk prostate cancer. * ≤20 ng/ml PSA. * PSA density ≤0.15 * ≥50 years of age; with life expectancy of ≥10 years. * Clinical cancer stage less than or equal to T2c (tumor may involve both sides of the prostate but without evidence that tumor extends outside of the prostate and with no cancer cells found in nearby lymph nodes) evaluated by PSMA PET scan. * Within 6 months prior to signing consent have had a multiparametric MRI. 1. mpMRI results must show localized disease meaning a single MRI region of suspicion (PI-RADS ≥3 with lesion volume ≤1.5 cc). 2. Maximum lesion diameter in any MRI dimension must be ≤11.9 mm. * Within 6 months prior to signing consent, have undergone a multiparametric MRI software guided fusion biopsy of the prostate (transrectal or transperineal) 1. Central Pathology confirmation showing a minimum of 2 cores in aggregate of pattern 4 disease (GG3) in the targeted lesion identified by Central Imaging 2. GG1 cores from anywhere in the prostate are acceptable 3. Less than 50% of systematic biopsy cores are positive for GGG 1 or 2 disease. For the \