Minimally invasive surgery versus laparotomy of non-metastatic pT4a colorectal cancer: a propensity score analysis

Aim: To compare short- and long-term oncological outcomes between minimally invasive surgery (MIS group) and laparotomy (lap group) in non-metastatic pT4a colorectal cancer (CRC). Materials and Methods: The study retrospectively analyzed outcomes of 634 patients treated with radical operation from January 2015 to December 2021 for non-metastatic pT4a CRC, with propensity score matching. Results: Conversion rate from minimally invasive surgery group to laparotomy is 3.5%. Intraoperative blood loss, time to first anal exhaust, defecation and drainage tube removal, and complication rate were significantly less in the minimally invasive surgery group. After 5 years, the outcomes of MIS group were no inferior to laparotomy outcomes (overall survival: 72.7% vs. 77.8%, P =0.285; disease-free survival: 72.2% vs. 75.0%, P =0.599). And multivariate analysis showed that age ≥60 years old, lymph node metastasis and the CEA levels were independent variables for OS, while lymph node metastasis and CA125 levels were independent variables for DFS. The results of the graph show the relationship between the sum of scores of gender, age, complications, BMI, CEA, age, CA125, tumor site, N stage and tumor length diameter and 1-year, 3-year and 5-year mortality and disease-free survival of patients. Among them, tumor length diameter and N stage are significantly correlated with long-term survival and disease-free of patients. Conclusion: Minimally invasive surgery is safe and feasible for non-metastatic pT4a CRC, with the added benefit of accelerated post-operative recovery. In oncology, minimally invasive surgery did not affect overall survival and disease-free survival.