Description of Surgical Technique and Oncologic and Functional Outcomes of the Precision Prostatectomy Procedure (IDEAL Stage 1-2b Study)

Abstract

Background: The existing treatment options for men with intermediate- or high-volume low-risk prostate cancer (PCa) are associated with a substantial risk of over- or undertreatment. The development of risk-adjusted therapies is an unmet need for these patients.

Objective: To describe our novel technique of precision prostatectomy, a form of surgical focal therapy that allows radical excision of the index PCa lesion along with >90% prostatic tissue extirpation while preserving the prostatic capsule and seminal vesicle/vas deferens complex on the side contralateral to the dominant cancer lesion, and to report on medium-term functional and oncologic outcomes in the first 88 consecutive men who underwent this procedure between December 2016 and January 2020.

Design, setting, and participants: Men with (1) prostate-specific antigen (PSA) ≤20 ng/ml, (2) clinical T stage ≤cT2, (3) a dominant unilateral lesion with Gleason ≤ 4 + 3 disease with any number or percentage of cores involved ipsilaterally on prostate biopsy, (4) no primary Gleason ≥4 lesion contralaterally, and (5) a preoperative Sexual Health Inventory of Men (SHIM) score of ≥17 (out of 25) with/without phosphodiesterase type-5 inhibitor use who consented to undergo precision prostatectomy were included in this single-arm, single-center, IDEAL stage 2b prospective development study.

Intervention: Robotic precision prostatectomy.

Outcome measurements and statistical analysis: The safety and urinary, sexual, and oncologic outcomes of the precision prostatectomy technique were studied. Descriptive statistics and Kaplan-Meier analyses were used to assess 12-mo urinary continence (0-1 pad), 12-mo sexual potency (SHIM score ≥17), 36-mo freedom from clinically significant PCa (grade group ≥2), secondary treatments, metastatic disease, and mortality.

Results and limitations: At study entry, the median age, PSA, and SHIM score were 60.0 yr (interquartile range [IQR] 54.2-65.9), 5.7 ng/ml (IQR 4.2-7.1), and 22 points (IQR 19-24), respectively. The median follow-up was 25 mo (IQR 14-38). At 12 mo, all patients were continent (0-1 pads), with 90.9% of patients using 0 pads. The median time to urinary continence was 1 mo (IQR 1-4). At 12 mo, 85% of all-comers and 90.2% of the preoperatively potent men were potent. The median time to sexual potency was 4 mo (IQR 4-12). From an oncologic standpoint, at 36 mo an estimated 93.4% of the patients were free from clinically significant residual PCa and 91.7% had not undergone any additional treatment. All patients were alive and free of metastatic disease at 36 mo.

Conclusions: Precision prostatectomy is technically safe and reproducible and offers excellent postoperative functional results. At 36-mo follow-up, the oncologic outcomes and secondary treatment rates appear to be superior to existing ablative focal therapy results. Pending long-term data, a risk-stratified surgical approach to PCa may avoid whole-gland therapy and preserve functional quality of life in men with localized PCa.

Patient summary: Precision prostatectomy is a new form of focal therapy for intermediate-risk prostate cancer in which a 5-10-mm rim of prostate capsule is left on the opposite side of the gland to where the dominant cancer is located. The technique appears to be safe and efficacious and adds to the growing armamentarium of risk-adapted therapies for treatment of localized prostate cancer that avoid the adverse effects on urinary and erectile function of whole-gland treatments.

Keywords: Erectile dysfunction; Focal therapy; Minimally invasive surgical procedures; Prostate cancer; Prostatectomy; Robotics; Urinary incontinence.