Long-term oncologic outcomes following anastomotic leak after anterior resection for rectal cancer: does the leak severity matter?

Background The evidence regarding the impact of anastomotic leak (AL) after anterior resection (AR) for rectal cancer on oncologic outcomes is controversial, and there are no data about the prognostic relevance of the International Study Group of Rectal Cancer (ISREC) AL classification. The aim was to evaluate the oncologic outcomes in patients with AL after AR for rectal cancer. The prognostic value of the ISREC AL grading system was also investigated. Methods It is a retrospective analysis of a prospectively collected database including all patients undergoing curative elective AR for rectal cancer (April 1998–September 2013). AL severity was defined according to the ISREC criteria. A multivariable analysis was performed to identify predictors of poor survival. Results A total of 532 patients underwent curative AR (69% laparoscopic) for rectal cancer. The overall AL rate was 7.9%: 15 grade B and 27 grade C ALs. With a median follow-up of 80 (range 12–266) months, 5-year overall survival (OS) was 67.2% in patients with AL and 86.5% in those without AL ( P = 0.001). Five-year disease-free survival (DFS) was 50.5% and 80.3%, respectively ( P < 0.001). Local recurrence and distant metastases developed more frequently in AL patients ( P < 0.05). Grade B AL and no administration or delay of adjuvant chemotherapy were independent predictors for poorer OS and DFS. Grade B AL independently affected also the administration of adjuvant chemotherapy. Circulating C-reactive protein levels at 2 weeks after AL treatment were higher in grade B than grade C patients ( P = 0.006) and in patients with tumor relapse ( P = 0.011). Conclusion AL after curative AR for rectal cancer and impaired use of adjuvant chemotherapy are associated with poor survival. Postoperative systemic inflammation seems to be more sustained in grade B than that in grade C AL patients, with possible adverse impact on long-term survival.