Clinical characteristics of anastomotic leakage after an anterior resection for rectal cancer by assessing of the international classification on anastomotic leakage

The International Study Group of Rectal Cancer (ISREC) has proposed a new definition of anastomotic leakage (AL) which was simply classified into three grades; however, these criteria have not been assessed well. The aims of this study are to assess the new definition and to show the clinical features of AL after an anterior resection for rectal cancer. Fifty consecutive patients developed AL after an anterior resection for rectal cancer was retrospectively assessed. AL was defined by the ISREC criteria. Twenty-seven (54 %) patients with AL were diagnosed by drain contents. The postoperative day of diagnosis for AL was later in grade A versus grades B and C (p = 0.038 vs p = 0.006, respectively). Permanent stoma (PS) was significantly more frequent in patients with grade C but not grade B compared to the patients with no AL (p < 0.001 and p = 0.171, respectively). In patients without diverting stoma, there was more serious grade of AL (p < 0.001). Differences were observed in the postoperative day of diagnosis, the creation rate of PS, and impact on diverting stoma after AL between each grade of leakage. The new classification was easy and reasonable to evaluate AL. As a result, it should be widely used in future studies.