Does postoperative morbidity worsen the oncological outcome after radical surgery for gastrointestinal cancers? A systematic review of the literature

Purpose: The impact of postoperative complications on survival after radical surgery for esophageal, gastric, and colorectal cancers remains controversial. We conducted a systematic review of recent publications to examine the effect of postoperative complications on oncological outcome. Methods: A literature search of PubMed/MEDLINE was performed using the keywords "esophageal cancer," "gastric cancer," and "colorectal cancer," obtaining 27 reports published online up until the end of April 2016. Articles focusing on (i) post-operative morbidity and oncological outcome; and (ii) body mass index (BMI), postoperative morbidity, and oncological outcome, were selected. Univariate and multivariate analyses (Cox proportional hazards model) were performed. Results: Patients with postoperative complications had significantly poorer long-term survival than those without complications. Complications were associated with impaired oncological outcomes. The hazard ratios for overall survival were 1.67 (95% confidence interval [CI], 1.31-2.12), 1.59 (95% CI, 1.13-2.24), and 1.55 (95% CI, 1.28-1.87) in esophageal, gastric, and colorectal cancers, respectively. High BMI was associated with postoperative morbidity rate but not with poor oncological outcome. Low BMI was significantly associated with inferior oncological outcome. Conclusions: Complications after radical surgery for esophageal, gastric, and colorectal cancers are associated with patient prognosis. Avoiding such complications might improve the outcomes.