[Analysis of risk factors of severe postoperative complications in elderly patients with colorectal cancer aged over 80 years]

Objective: To investigate the risk factors of severe postoperative complications in elderly patients with colorectal cancer aged over 80 years old. Methods: A retrospective case-control study was conducted to collect and analyze the clinicopathological data of patients (≥80 years old) who underwent radical colorectal cancer surgery at department of Colorectal Surgery, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College from January 2010 to December 2018. A total of 269 patients were included in the study, including 160 males and 109 females. The average age was 83 (80-94) years. Among them, the pathological TNM stage was 16 in stage I, 76 in stage II, 167 in stage III, and 10 in stage IV. According to Clavien-Dindo classification, the postoperative complications of grade III and above were defined as serious complications. To analyze the relationship between the patient's clinical data, such as general information, the surgeon's experience (whether to complete more than 500 radical colorectal cancer surgery), intraoperative conditions and the occurrence of severe complications. Univariate analysis was conducted with the chi-squared test. Multivariate logistic regression analysis was used for statistically significant variables in univariate analysis. Results: Of the 269 patients, 34 (12.6%) had severe complications after surgery. The incidence of postoperative complications ranged from high to low, respectively, for pulmonary infection (8/269,3.0%), intestinal obstruction (8/269, 3.0%) and anastomotic leakage (7/269, 2.6%). One patient died of pulmonary embolism and one patient died of multiple organ failure, with a perioperative mortality rate of 0.7% (2/269). On univariate analysis, the occurrence of severe postoperative complications was associated with age (χ(2)=8.181, P=0.004), American society of anesthesiologists grade (χ(2)=7.945, P=0.005), preoperative albumin level (χ(2)=9.088, P=0.003), operation experience (χ(2)=9.395, P=0.002). Multivariable logistic regression analysis showed that age ≥85 years old (OR=4.415, 95% CI: 1.702-11.453, P=0.080), preoperative albumin <35 g/L (OR=2.544, 95%CI: 1.083-5.974, P=0.032), and less-experieced group (OR=2.475, 95% CI:1.082-5.661, P=0.032) was independent risk factor for severe postoperative complications. The incidence of serious postoperative complications was similar in patients undergoing laparoscopy and laparotomy [10.1% (17/169) vs. 17.0% (17/100), χ(2)=2.741, P=0.098]. Conclusion: Adequate preoperative evaluation, appropriate perioperative nutritional support and experienced specialists are the key factors to ensure the successful perioperative period of elderly patients with colorectal cancer aged over 80 years old. In addition, more attention should be paid to the elderly patients aged ≥85 years.