Comparison of Perioperative, Functional, and Oncological Outcomes of Transperitoneal and Extraperitoneal Laparoscopic Radical Prostatectomy

PURPOSE: This study aimed to compare the oncological, functional, and perioperative outcomes of localized and locally advanced prostate cancer treated with intraperitoneal or extraperitoneal laparoscopic radical prostatectomy (LRP). METHODS: From April, 2008, through December, 2020, 266 patients underwent laparoscopic radical prostatectomy, 168 cases with an extraperitoneal approach (E-LRP) and 98 cases using a transperitoneal approach (T-LRP). The clinical, perioperative, functional, and oncological outcomes were collected and compared between these groups. At the 3-, 12- and 24-monthfollow-ups, the functional outcomes tested were urinary function (urinary domain of EPIC) and sexual function (sexual domain of EPIC). The oncological outcomes of biochemical recurrence, biochemical recurrence-free survival, and positive surgical margin status were evaluated. Univariable and multivariable Cox regression analyses were used to identify factors predictive for biochemical recurrence. All statistical analyses used the R program. RESULTS: The patient characteristics were similar between the E-LRP and T-LRP groups except for higher prostatic-specific antigen (PSA) in the T-LRP group. The T-LRP had lower overall operative time (222.5 min vs. 290 min, p 0.001), decreased blood loss (400 ml vs. 800 ml, p < 0.001), and shorter hospital stays (4 days vs. 7 days, p < 0.001) compared to the E-LRP. Early sexual intercourse with penetration at 3 months was higher in the T-LRP group (36.7% vs. 15.5%, p 0.001). Urinary continence (no pads) was not different between the T-LRP and E-LRP groups at 3 and 24 months after surgery but higher in the E-LRP group at 12 months (1% vs. 3%; p=0.419, 85.1 vs. 83.7%; p=0.889, 47.4% vs. 34.6%; p=0.028, respectively). The EPIC questionnaire was used to assess functional outcomes at 3, 12, and 24 months after surgery and found that urinary function was significantly higher in the T-LRP group at 3 and 12 months (p < 0.001) but did not show a difference at 24 months (p=0.734), and sexual function scores were higher in the T-LRP group at 12 and 24 months (p=0.001). The positive surgical margin rate was higher in the E-LRP (38.7% vs. 21.4%; p=0.006). The BCR rate was not different between the groups (36.3% in the E-LRP group and 27.6% in the E-LRP group; p=0.184). CONCLUSION: Transperitoneal laparoscopic radical prostatectomy (T-LRP) was found to be superior to extraperitoneal radical prostatectomy (E-LRP) in perioperative outcomes such as decreased operative time, decreased blood loss, shorter hospital stay, lower positive surgical margin, and improved early sexual intercourse and sexual function. The urinary functional outcome was better in the T-LRP group at 3 and 12 months. These findings support the use of transperitoneal laparoscopic radical prostatectomy, as our study patients exhibited significant benefits from this procedure.