A total of ten original articles met the inclusion criteria for the present narrative review, all of which adopted a retrospective study design [6, 9,10,11,12,13,14,15,16,17]. The SP Transvesical technique was the most popular approach and was described in nine studies [6, 9, 10, 13,14,15,16,17]. In contrast, the Extraperitoneal and Transperitoneal approaches were reported in two studies with a total of 26 patients and one study involving 46 patients, respectively [10,11,12]. The perioperative and postoperative outcomes reported by the different studies were summarized in Table 1.

Following the report of the initial clinical experience by Kaouk et al. in 2020, Transvesical SP-RARP has since been performed in 258 patients according to the most up-to-date data from the Single Port Advanced Research Consortium (SPARC). Based on the data reported in the included studies, Transvesical SP-RARP, also often referred to as the SP Transvesical Enucleation of the Prostate (STEP), was commonly performed in large prostate glands with a median preoperative prostate volume ranging between 105 and 185 mL, and upwards to 350 mL. As highlighted in Table 1, the most common surgical indications included urinary retention and suboptimal response to the medical treatments for BPH, which were reported in up to 68% and 54% of the patients, respectively [6, 9, 10, 13,14,15,16,17].

In terms of perioperative outcomes, all procedures were completed without the need for an additional port or evidence of surgical conversion. Most of the cases appeared to be completed within 180 min with the largest multi-institutional case series by Abou Zeinab et al. involving 110 patients reporting a median total operating time of 160 min. Intraoperative blood loss also remained negligible with most studies indicating the median estimated blood loss (EBL) ranging between 100 and 150 mL [6, 9, 10, 13,14,15,16,17]. Despite the very low incidence, intraoperative complication was reported in four patients, all of which were related to venous air embolism, with clinical manifestations including hemodynamic instability as well as the sudden drop in oxygen saturation and end-tidal CO2. All four cases were managed conservatively with supportive therapy and without any additional intervention or further clinical sequelae [6, 10, 13, 14, 17].

Postoperatively, the placement of a surgical drain or the commencement of continuous bladder irrigation was not routinely indicated. Of note, throughout our clinical experience, the standard of clinical practice involves the placement of a two-way urinary catheter at the end of the procedure, which can be removed as early as three days following the respective surgery and with a median postoperative urinary catheter duration ranging between 3 and 7 days. Following catheter removal, most patients reported favorable outcomes as indicated by the significant improvements in their International Prostate Symptom Score (IPSS), Quality of Life (QoL) scores, as well as their uroflowmetry results, especially with the negligible postoperative post-void residual (PVR) volume and a maximum flow rate (Qmax) above 20 mL/s reported in most patients. With regards to postoperative morbidity, the incidence of postoperative complications remained relatively low, with all cases pertaining to minor complications of Clavien Grades 1 and 2. Furthermore, most studies also reported either the alleviated or reduced risk of transient postoperative urinary incontinence following the STEP procedure, ranging between 0–12.1% [6, 9, 10, 13,14,15,16,17].

Of the different studies included in this review, six studies included a comparison analysis between SP-RASP and other treatment modalities, including open simple prostatectomy (OSP), MP-RASP, as well as endoscopic laser enucleation techniques (Table 2) [6, 10, 11, 14, 15, 17]. Compared to OSP, the SP Transvesical approach provided additional benefits in improving perioperative morbidity, especially with the significant reduction in intraoperative blood loss (median, STEP 150 vs. OSP 400 mL), the need for surgical drain (STEP 0% vs. OSP 100%), and continuous bladder irrigation (STEP 0% vs. OSP 100%), as well as reducing the risk of major postoperative complications (STEP 0% vs. OSP 11.6%). Despite the relatively similar functional outcomes, such as in terms of the perioperative changes in uroflowmetry parameters, the SP technique remained superior in shortening Foley catheter duration (median, STEP 7 vs. OSP 10 days) and the risk of de novo urinary incontinence (STEP 3% vs. OSP 11.4%) [6]. Similar findings were also observed when comparing SP and MP-RASP, especially with the reduced need for surgical drain and continuous bladder irrigation, as well as the reduced postoperative pain following the regionalized SP approach that translated to an enhanced postoperative recovery with reduced length of stay and allowing for the increased adoption of opioid-sparing outpatient procedures [10, 11, 17].

In addition, we have also identified two studies comparing the STEP procedure with the endoscopic enucleation techniques, including the Holmium Laser Enucleation of the Prostate (HoLEP) and Thulium Laser Enucleation of the Prostate (ThuLEP). While the perioperative and functional outcomes between the procedures were noted to be similarly favorable, the SP Transvesical approach continued to maintain improved postoperative continence outcomes. Notably, Palacios et al. reported a 3-month incidence of postoperative de novo urinary incontinence of 5% and 28% for STEP and HoLEP, respectively, while Talamini et al. identified an overall incidence of postoperative urinary incontinence of 12.1% following STEP versus 21.7% after ThuLEP [14, 15].