Application value of laparoscopic surgery in elderly patients (≥ 75 years) with colorectal cancer and prognostic factors influencing 5-year overall survival.

OBJECTIVE

To investigate the application value of laparoscopic surgery in elderly patients (≥ 75 years) with colorectal cancer, and to identify the prognostic factors influencing the long-term survival in this demographic, and to establish a predictive nomogram model.

METHODS

A retrospective analysis was conducted on 146 elderly (≥ 75 years old) colorectal cancer patients who underwent radical surgery in Baoji People's Hospital from August 2016 to February 2018, including 55 patients who underwent laparotomy and 91 patients who underwent laparoscopic surgery. Survival curves were plotted using the Kaplan-Meier method, and differences in prognosis were assessed using the Log-rank test. Prognostic impacts of various factors on 5-year survival were analyzed using a Cox proportional hazards model. Significant predictors identified in the Cox model were used to construct a nomogram for predicting survival, which was then validated for accuracy and clinical utility.

RESULTS

Laparoscopic surgery was associated with shorter hospital stays (P = 0.022), although at a higher cost (P = 0.011). The laparoscopic group also had less intraoperative bleeding (P < 0.001), incision length (P < 0.001), time to first postoperative expectoration (P < 0.001), time to first postoperative feeding (P = 0.002), and time to postoperative peritoneal drainage (P = 0.003) compared to the open surgery group. Additionally, the rate of postoperative wound complications was also lower in the laparoscopic group (P = 0.014). There was no significant difference in the 5-year post-treatment survival between the two groups (P = 0.150). Multifactorial Cox regression analysis revealed that a history of diabetes mellitus (P = 0.037), vascular infiltration (P = 0.026), nerve bundle invasion (P = 0.001), and TNM stage (P = 0.001) were independent prognostic factors affecting the 5-year survival of patients with advanced colorectal cancer. The constructed nomogram showed high predictive accuracy for 1-, 3-, and 5-year survival, with AUC values of 0.91, 0.87, and 0.79, respectively. Calibration curves and decision curve analysis confirmed the model's clinical utility. Risk formula: History of diabetes mellitus * -0.696194503 + Vascular infiltration * -0.769736513 + Nerve bundle invasion * -1.1709777 + TNM staging * 1.201933691.

CONCLUSION

Laparoscopic surgery can reduce intraoperative trauma and accelerate postoperative recovery in elderly colorectal cancer patients (≥ 75 years) compared to open surgery. The developed nomogram model based on independent prognostic factors such as diabetes history, vascular infiltration, nerve bundle invasion, and TNM staging, facilitates tailored prognostic assessment, enhancing individual patient management.