Does oncological outcome differ between restorative and nonrestorative low anterior resection in patients with primary rectal cancer?

AIM: Nonrestorative low anterior resection (n‐rLAR) (also known as low Hartmann’s) is performed for rectal cancer when a poor functional outcome is anticipated or there have been problems when constructing the anastomosis. Compared with restorative LAR (rLAR), little oncological outcome data are available for n‐rLAR. The aim of this study was to compare oncological outcomes between rLAR and n‐rLAR for primary rectal cancer. METHOD: This was a nationwide cross‐sectional comparative study including all elective sphincter‐saving LAR procedures for nonmetastatic primary rectal cancer performed in 2011 in 71 Dutch hospitals. Oncological outcomes of patients undergoing rLAR and n‐rLAR were collected in 2015; the data were evaluated using Kaplan–Meier survival analysis and the results compared using log‐rank testing. Uni‐ and multivariable Cox regression analysis was used to evaluate the association between the type of LAR and oncological outcome measures. RESULTS: A total of 1197 patients were analysed, of whom 892 (75%) underwent rLAR and 305 (25%) underwent n‐rLAR. The 3‐year local recurrence (LR) rate was 3% after rLAR and 8% after n‐rLAR (P < 0.001). The 3‐year disease‐free survival and overall survival rates were 77% (rLAR) vs 62% (n‐rLAR) (P < 0.001) and 90% (rLAR) vs 75% (n‐rLAR) (P < 0.001), respectively. In multivariable Cox analysis, n‐rLAR was independently associated with a higher risk of LR (OR = 2.95) and worse overall survival (OR = 1.72). CONCLUSION: This nationwide study revealed that n‐rLAR for rectal cancer was associated with poorer oncological outcome than r‐LAR. This is probably a noncausal relationship, and might reflect technical difficulties during low pelvic dissection in a subset of those patients, with oncological implications.