Does intestinal anastomosis in resection of colon cancer have a significant impact onto early postoperative outcome and long-term survival?

Objectives: To investigate the influence of anastomosis on the early postoperative and long-term oncological outcomes of patients with primary colon carcinoma (CA). Methods: All consecutive patients with the histologically diagnosed primary colon CA (design, prospective multicenter observational study) were registered with regard to patient-, diagnostic-, tumor (Tu) finding-, and treatment-related aspects using a computer-based registry with 60 items to characterize early postoperative and long-term oncological outcome. Results: Basic data: From 2010 to 2016, data from a total of 14,466 patients were documented (mean age, 72.8 [range, 22-96] years; sex ratio, m:f=7,696:6,770). - 717/14,466 patients (4.96 %) were included in a matched-pair analysis. The majority of these patients underwent elective surgery (n=12,620 patients; 87.2 %) regardless of whether a bowel anastomosis or an ostomy was created. In emergency surgery, a bowel anastomosis was possible in a large proportion (n=1,332 patients [72.1 %]). In contrast, in 514 patients (27.9 %) who underwent emergency surgery, an ostomy was created. Interestingly, ostomy had to be created even less frequently in patients who had undergone planned surgery (n=366 [2.5 %]). - Early postoperative outcome: Cases of postoperative mortality were mainly due to general complications. Especially among the patients treated in an emergency situation without intestinal anastomosis, a high proportion died of their pre-existing condition (17.0 %). Patients who underwent ostomy creation or emergency surgery had a worse risk profile (incl. arterial hypertension, diabetes mellitus, and secondary cardiac or renal diseases) which led to the decision to operate without anastomosis. Furthermore, data show no matter which technique had been used, patients that had undergone surgical intervention without anastomosis were more likely to develop complications. - Long-term oncosurgical outcome: The most important factors influencing long-term survival were age, resection status, and tumor stage (according to TNM and UICC). The more advanced the tumor growth, the lower the long-term survival. Patients categorized with the same tumor stage, age, and risk factors had a better chance of survival, if they underwent elective surgical intervention and with intestinal anastomosis. Interestingly, the multivariable analysis showed that older patients and such with distant metastasis benefit from a discontinuity resection. Conclusions: The association of intraoperative and postoperative complications with increased postoperative mortality, as well as preexisting risk factors and perioperative complications is in line with findings of current studies. Furthermore, current studies also agree that older patients and such with reduced general condition benefit from discontinuity resection.