Oncological impact of anastomotic leakage after laparoscopic mesorectal excision.

Background: The effect of anastomotic leakage on oncological outcomes after total mesorectal excision (TME) is controversial. This study aimed to assess the influence of symptomatic and asymptomatic anastomotic leakage on oncological outcomes after laparoscopic TME.

Methods: All patients who underwent restorative laparoscopic TME for rectal adenocarcinoma with curative intent from 2005 to 2014 were identified from an institutional database. Asymptomatic anastomotic leakage was defined by CT performed systematically 4-8 weeks after rectal surgery, with no relevant clinical symptoms or laboratory examination findings during the postoperative course.

Results: Of a total of 428 patients, anastomotic leakage was observed in 120 (28·0 per cent) (50 asymptomatic, 70 symptomatic). After a mean follow-up of 40 months, local recurrence was observed in 36 patients (8·4 per cent). Multivariable Cox regression identified three independent risk factors for reduced local recurrence-free survival (LRFS): symptomatic anastomotic leakage (odds ratio (OR) 2·13, 95 per cent c.i. 1·29 to 3·50; P = 0·003), positive resection margin (R1) (OR 2·41, 1·40 to 4·16; P = 0·001) and pT3-4 category (OR 1·77, 1·08 to 2·90; P = 0·022). Patients with no risk factor for reduced LRFS had an estimated 5-year LRFS rate of 87·7(s.d. 3·2) per cent, whereas the rate dropped to 75·3(4·3) per cent with one risk factor, 67(7) per cent with two risk factors, and 14(13) per cent with three risk factors (P < 0·001). Asymptomatic anastomotic leakage was not significantly associated with LRFS in multivariable analysis.

Conclusion: Symptomatic anastomotic leakage is a risk factor for disease recurrence in patients with rectal adenocarcinoma.