What is the Impact of Comorbidities in the Outcomes of Minimally Invasive Surgery for Elderly Patients With Colorectal Cancer?

Background: Comorbidity burden may influence perioperative outcomes in elderly patients undergoing minimally invasive resection for colorectal cancer (CRC). This study evaluated the association between the Charlson Weighted Comorbidity Index (CCI) and short-term postoperative outcomes in this population. Methods: A retrospective review of 894 consecutive patients aged 65 years or older who underwent curative minimally invasive resection for CRC at a single institution between January 2014 and August 2023. Surgical approaches included pure laparoscopic, robotic-assisted, and converted-to-open procedures. Comorbidity burden was quantified using the CCI, excluding age and the index colorectal malignancy from score calculation. Patients with and without postoperative complications were compared, and multivariable logistic regression was performed to identify independent factors associated with complications. Patients were divided into 2 groups [low CCI (≤2; n=637) and high CCI (≥3; n=257)] to investigate the relationship between an increased CCI score and the patients’ short-term outcomes. Results: Postoperative complications occurred in 319 patients (36%). Age, American Society of Anesthesiologists Physical Status (ASA) score, conversion to open surgery, rectal tumor location, and CCI score were significantly higher in patients with postoperative complications. On multivariable analysis, age 75 years or older, ASA score ≥4, conversion to open surgery, rectal tumor location, and CCI ≥3 were independently associated with an increased risk of postoperative complications. The discriminatory ability of CCI alone was modest (AUC: 0.578). Compared with the low-CCI group, the high-CCI group had higher rates of transfusion (13% vs. 8%, P =0.016), overall complications (46% vs. 31%, P <0.001), and 30-day mortality (2% vs. 1%, P =0.024), as well as a longer postoperative length of stay (6.4 vs. 5.2 days, P <0.001). Conclusion: Higher comorbidity burden, as measured by CCI, was associated with worse short-term postoperative outcomes after minimally invasive CRC surgery in elderly patients. Although CCI alone showed limited discriminatory performance for individual prediction, a CCI score ≥3 identified a subgroup with substantially higher postoperative risk and may potentially be useful as a simple adjunct in preoperative risk assessment.