The surgical learning curve for robotic-assisted laparoscopic radical prostatectomy: Experience of a single surgeon with 500 cases in Taiwan, China

To analyze the learning curve for cancer control from an initial 250 cases (Group I) and subsequent 250 cases (Group II) of robotic-assisted laparoscopic radical prostatectomy (RALP) performed by a single surgeon. Five hundred consecutive patients with clinically localized prostate cancer received RALP and were evaluated. Surgical parameters and perioperative complications were compared between the groups. Positive surgical margin (PSM) and biochemical recurrence (BCR) were assessed as cancer control outcomes. Patients in Group II had significantly more advanced prostate cancer than those in Group I (22.2% vs 14.2%, respectively, with Gleason score 8-10, P= 0.033; 12.8% vs 5.6%, respectively, with clinical stage T3, P= 0.017). The incidence of PSM in pT3 was decreased significantly from 49% in Group I to 32.6% in Group II. A meaningful trend was noted for a decreasing PSM rate with each consecutive group of 50 cases, including pT3 and high-risk patients. Neurovascular bundle (NVB) preservation was significantly influenced by the PSM in high-risk patients (84.1% in the preservation group vs 43.9% in the nonpreservation group). The 3-year, 5-year, and 7-year BCR-free survival rates were 79.2%, 75.3%, and 70.2%, respectively. In conclusion, the incidence of PSM in pT3 was decreased significantly after 250 cases. There was a trend in the surgical learning curve for decreasing PSM with each group of 50 cases. NVB preservation during RALP for the high-risk group is not suggested due to increasing PSM.