Pragatheeshwar Thirun, Emmanuel Gabriel, Steven J Nurkin. Roswell Park Cancer Institute
Introduction: Robotic proctectomy (RP) is an increasingly adopted alternative for minimally invasive rectal resections. Our objective was to compare the nationwide surgical outcomes between robotic and laparoscopic proctectomies (LC).
Methods: We extracted data for all patients who underwent minimally invasive (laparoscopic or robotic) proctectomies for rectal adenocarcinoma between 2010 and 2011 from the National Cancer Database (NCDB).
Results: Of the total 6,478 patients who had minimally invasive proctectomies, 1182 (18.2%) patients underwent RP and the remaining 5,296 (81.8%) underwent LP. The proportion of minimally invasive rectal resections performed robotically increased from 15.5% in 2010 to 20.6% in 2011 (P<.001). 73.8% underwent partial rectal resections (anterior and low anterior resection), 16.9% underwent abdominoperineal resection (APR), and 9.3% underwent total proctectomy with pull-through procedure (coloanal anastomosis). Patients who underwent RP had higher rates of neoadjuvant treatment compared to LP (46.4% vs 61.8%, P<.001). The cohorts for LP and RP were slightly different in median age (62 vs.61 years, P<.001) but not different in sex (P=.14), race (P=.25), Charlson-Deyo comorbidity score (P=.19) or tumor size (P=.90). Among LPs, 74.8% were partial resections, 15.9% were APRs and 9.3% were pull-through procedures, whereas among RPs, 69.5% were partial resections, 21.6% were APRs and 8.9% were pull—through procedures. Operative outcomes for RP and LP were similar in terms of margin positive rate (4.6% vs 5.2%, P=.48), retrieval of fewer than 12 lymph nodes (31.8% vs. 32.1%, P=.85), median postoperative stay (5 vs. 5 days, P= .54), and unplanned 30-day readmission rate (7.8% vs 7.3%, P=.56). Conversion rate to open surgery was higher with LP compared to RP (17.4% vs. 9.7%, P<.001). Compared to surgeries completed minimally invasively, those converted to open had a higher readmission rate (7.1% vs. 8.9%, P=.04), higher margin positive rate (4.8% vs. 6.9%, P=.001), longer hospital stay (5 days vs. 6 days, P<.001), time to adjuvant therapy (47 days vs. 52 days, P=.04) and 30-day mortality (1.1% vs. 1.9%, P=.03). Overall 30-day mortality was also higher with LP than RP (1.3% vs. 0.6%, P =.05).
Conclusions: Robotic surgery is being increasingly used for rectal cancer. preferentially for APRs and pull-through procedures. Compared to the laparoscopic approach, robotic proctectomies provided equivalent surgical outcomes for rectal cancer patients. ompared to the laparoscopic approach, the robotic approach is associated with a significantly lower conversion rate to open surgery, which in turn contributed to decreased hospital stay, readmission rate, margin positive resection and 30-day mortality.