Evolution of minimally invasive surgery for rectal cancer: update from the national cancer database

As the use of minimally invasive techniques in colorectal surgery has become increasingly prevalent, concerns remain about the oncologic effectiveness and long-term outcomes of minimally invasive low anterior resection (MI-LAR) for the treatment of rectal cancer.

The 2010-2015 National Cancer Database (NCDB) Participant Data Use File was queried for patients undergoing elective open LAR (OLAR) or MI-LAR for rectal adenocarcinoma. A 1:1 propensity match was performed on the basis of demographics, comorbidity, and tumor characteristics. Outcomes were compared between groups and Cox proportional hazard modeling was performed to identify independent predictors of mortality. A subset analysis was performed on high-volume academic centers.

35,809 patients undergoing LAR were identified of whom 18,265 (51.0%) underwent MI-LAR. After propensity matching, patients receiving MI-LAR were less likely to have a positive circumferential radial margin (CRM) (5.5% vs. 6.6%, p = 0.0094) or a positive distal margin (3.6% vs. 4.6%, p = 0.0022) and had decreased 90-day all-cause mortality (2.0% vs. 2.6%, p = 0.0238). MI-LAR resulted in decreased hospital length of stay (5 vs. 6 days, p < 0.0001) but a greater rate of 30-day readmission (7.6% vs. 6.5%, p = 0.0054). Long-term overall survival was improved with MI-LAR (79% vs. 76%, p < 0.0001). Cox proportional hazard modeling demonstrated a decreased risk of mortality with MI-LAR (HR 0.859, 95% CI 0.788-0.937).

MI-LAR is associated with improvement in CRM clearance and long-term survival. In the hands of experienced surgeons with advanced laparoscopy skills, MI-LAR appears safe and effective technique for the management of rectal cancer.