Abstract

Objective (s)： This study aims to identify independent risk factors for anastomotic leakage (AL) following laparoscopic colorectal cancer surgery through a single-center retrospective analysis, and to construct and validate a nomogram prediction model to guide early clinical intervention.

Methods: A total of 205 patients who underwent laparoscopic colorectal cancer radical surgery in our hospital from January to December 2023 were retrospectively included and divided into the AL group (n=39, 19.0%) and the non-AL group (n=166，81.0%).  Baseline characteristics (age, gender, BMI, comorbidities), tumor features (location), TNM staging, diameter, surgical parameters (operation time, intraoperative blood loss, preventive stoma), and postoperative inflammatory markers (CRP, PCT, WBC, albumin) were collected.  First, potential risk factors were identified by univariate analysis, followed by LASSO regression. Finally, independent risk factors were identified by multivariate Logistic regression analysis, and a nomogram model was constructed. The discriminatory ability, calibration effect, and clinical utility of the model were assessed using the receiver operating characteristic curve (ROC), calibration curve, and decision curve analysis (DCA), and were verified internally with the Bootstrap method (1000 repeated sampling).

Results: Patients in the AL group had significantly higher rates of preoperative hypoalbuminemia (48.72% vs 15.66%), longer operation time (397.74±112.36 min vs 275.83±83.92 min), greater intraoperative blood loss (349.74±179.56 ml vs 192.83±95.47 ml), and elevated postoperative inflammatory markers compared to the non-AL group.   Multivariate   analysis   identified   preoperative   hypoalbuminemia (OR=3.75, 95%CI: 1.68-8.36, P=0.001), operation time ≥360 minutes (OR=4.62, 95%CI: 2.14-9.98, P<0.001), postoperative day 1 CRP ≥60 mg/L (OR=6.34, 95%CI:2.75-14.62, P<0.001), and positive drainage fluid culture on postoperative day 3 (OR=7.12, 95%CI: 3.05-16.61, P<0.001) as independent risk factors for AL.  The comprehensive postoperative model based on these factors demonstrated optimal predictive performance (AUC=0.896, 95%CI: 0.842-0.950), with a corrected AUC of 0.872 (95%CI: 0.813-0.931)   after internal validation, outperforming both the preoperative model (AUC=0.738) and early postoperative model (AUC=0.832).

Conclusion: Preoperative hypoalbuminemia, prolonged operation time, significant early postoperative CRP elevation, and positive drainage fluid culture are independent risk factors for AL following laparoscopic colorectal cancer surgery. The nomogram model, constructed based on multi-timepoint indicators, effectively predicts AL risk, providing an essential basis for early identification of high-risk patients and implementation of individualized prevention strategies in clinical practice.