A Diagnostic Nomogram for Predicting the Risk of Anastomotic Leakage in Elderly Patients With Rectal Cancer: A Single-center Retrospective Cohort Study

Laparoscopic resection for rectal cancer has been gaining popularity over the past 2 decades. Whether elderly patients had more benefits from laparoscopy-assisted anterior resection (LAR) need further investigation when comparing with open anterior resection (OAR).This study aimed to evaluate the clinical outcomes and prognosis of LAR in elderly patients (65 y and above) with rectal cancer and investigate the factors associated with the anastomotic leakage (AL). Besides, the study sought to create a nomogram for precise prediction of AL after anterior resection for rectal cancer.A total of 343 rectal cancer patients over 65 years old who underwent LAR or OAR at a single center between January 2013 to January 2021 were retrospectively reviewed. Univariate analysis was conducted to explore potential risk factors for AL, and a nomogram for AL was created based on the multivariate logistic regression model.A total of 343 patients were included in this study, 271 patients in LAR group and 72 patients in OAR group. Most of the variables were comparable between the 2 groups. The mean operative time was longer in the LAR group than that in the OAR group (191.66±58.33 vs. 156.85±53.88 min, P<0.0001). The LAR group exhibited a significantly lower intraoperative blood loss than the OAR group (85.17±50.03 vs. 131.67±79.10 mL; P<0.0001). Moreover, laparoscopic surgery resulted in shorter postoperative hospital stay, lower rates of diverting stoma and receiving sphincter sparing surgery in comparison with open surgery. The overall rates of complications were 25.1% and 40.3% in the LAR and OAR groups (P=0.011), respectively. And the reoperation rates in the OAR group (0%) was lower than in the LAR group (1.5%), but the difference did not reach statistical significance (P=0.300). Sex, location of tumor, diverting stoma and combined organ resection were identified as independent risk factors for AL based on multivariate analysis. Such factors were selected to develop a nomogram. After a median follow-up of 37.0 months, our study showed no significant difference in overall survival or disease free survival between the 2 groups for treatment of rectal cancer.This study suggests that LAR is an alternative minimally invasive surgical procedure in patients above 65 years with better short-term outcomes and acceptable long-term outcomes compared with OAR. In addition, our nomogram has satisfactory accuracy and clinical utility may benefit for clinical decision-making.