Nerve spare robot assisted laparoscopic prostatectomy with amniotic membranes: medium term outcomes

dHACM is a source of factors including cytokines that allow anti-inflammatory and proliferative elements to be utilized for wound and ulcer management. We present our experience of using dHACM in a cohort of patients undergoing nerve-sparing (NS) robot-assisted laparoscopic prostatectomy (RALP). Our objective is to investigate the functional and oncological outcomes of NS after placing amniotic or dehydrated human amnion/chorion membrane (dHACM) on preserved neurovascular bundles (NVBs). From 2013 to 2019, our institution performed transperitoneal multi-port da Vinci robotic prostatectomy. The NVBs are spared by releasing their fascial planes posteriorly, followed by an anterior release of the plane at a similar level. Once the retrograde release of the NVB is performed then 599 patients underwent placement of dHACM graft (AmnioFix by MiMedx, Marietta, GA, USA). The graft was cut into two 4 × 1 cm pieces and laid over the NVB as a wrap. In order to inform the urological community of oncological and functional outcomes, we excluded patients with less than 12 months follow up (n = 64), benign prostatic hyperplasia (n = 5), and unilateral NS (n = 1). 529 (88%) patients were included in this study who underwent a partial or full bilateral NS with dHACM. 529 patients were followed-up for a median (IQR) of 42 months (25-89). Demographics include median (IQR) age 57 years (52-62), median preoperative SHIM score of 24 (21-15), and AUASS of 5 (2-11). Full NS was performed in 74% (391/529). Pathological staging was pT2 = 399 (75%), pT3a = 107 (20%), pT3b = 19 (4%) and pT4 = 4 (1%) with N1 = 3 (0.6%). The number of patients with PSM was 86 (16%), and the overall BCR in the entire cohort was 10%. Postoperatively, 434 (82%) were sexually active. Median time to potency was 119 (37-420) days and time to continence was 42 (23-91) days. Regarding full vs partial NS: median post op SHIM score 18 (13-20) vs 15 (6-20), median time to potency 92 (35-365) days vs 184 (42-560) days, and median time to continence 42 (23-91) days vs 44 (30-92) days. Age > 55 vs ≤ 55 years: median post op SHIM score 18 (12-20) vs 15 (10-20), median time to potency 167 days (42-549) vs 80 (35-288) days, and median time to continence 42 (25-116) days vs 42 (29-76) days. In our series the application of amniotic membrane/dHACM has led to acceptable post RALP outcomes. The BCR rate of 10% in addition to the recovery of potency at a median time of 3 months and continence at 6 weeks is an encouraging result of dHACM. Our findings indicate that dHACM allowed for an even faster period for continence recovery which was independent of grade of NS. Future comparative studies may further assess the impact of new amniotic membrane types on the functional and oncological outcomes after RALP.