Effects of surgical approach on short- and long-term outcomes in early-stage rectal cancer: a multicenter, propensity score-weighted cohort study

Background: Randomized controlled trials have been unable to demonstrate noninferiority of minimally invasive surgery for rectal cancer. The aim of this study was to assess oncologic resection success, short- and long-term morbidity, and overall survival by operative approach in a homogenous early-stage rectal cancer cohort. Methods: This is a multicenter, propensity score-weighted cohort study utilizing deidentified data from the National Cancer Database. Individuals who underwent a formal proctectomy for early-stage rectal cancer (T1-2, N0, M0) from 2010 to 2015 were included. The primary outcome was a composite variable indicating successful oncologic resection stratified by operative approach, defined as negative margins with at least 12 lymph nodes evaluated. Results: Among 3649 proctectomies for rectal adenocarcinoma, 1660 (45%) were approached open, 1461 (40%) laparoscopically, and 528 (15%) robotically. After propensity score weighting, compared to open approach, there were no differences in odds of successful oncologic resection (OR_adj = 1.07, 95% CI 0.9, 1.28 and OR_adj = 1.28, 95% CI 0.97, 1.7). Open approach was associated with longer mean (± SD) length of stay compared to laparoscopic (7.7 ± 0.18 vs. 6.5 ± 0.25 days, p < 0.001) and robotic (7.7 ± 0.18 vs. 6.3 ± 0.35 days, p < 0.001) approaches. In regard to 90-day mortality, compared to open approach, laparoscopic (OR_adj = 0.56, 95% CI 0.36, 0.88) and robotic (OR_adj = 0.45, 95% CI 0.22, 0.94) approaches were associated with a reduced odd of 90-day mortality. This mortality benefit persists in the long-term for laparoscopic approach (p = 0.003). Conclusion: For individuals with early-stage rectal cancer treated with proctectomy, successful oncologic resection can be achieved irrespective of technical approach. Minimally invasive approaches provide short-term reduction in morbidity. Surgical approach must be tailored to each patient based on surgeon experience and judgement in collaboration with a multi-disciplinary team.