Laparoscopic surgery is associated with increased risk of postoperative peritoneal metastases in T4 colon cancer: a propensity score analysis

Background: This study aims to evaluate the postoperative safety, long-term survival, and postoperative peritoneal metastases (PPM) rate associated with laparoscopic surgery (LS) for T4 colon cancer.

Materials and methods: After propensity score matching, there were 68 patients in each of the LS and Open surgery groups. The primary outcomes were the 3-year OS, DFS, and PPM rates.

Results: After matching, 68 patients in each of the groups. The LS group had a higher cumulative 3-year peritoneal metastasis rate (19.8% vs. 6.7%, P = .036), while the 3-year OS (82.3% vs. 83.8%, P = .750) and 2-year DFS (69.0% vs. 75.7%, P = .310) showed no significant difference, compared to the open surgery group. The LS group had a significantly longer operation time (201 ± 85.7 min vs. 164 ± 65.9 min, P = .008) but less postoperative complications (P = .036). Additionally, patients in the LS group removed gastric tube more quickly (1.91 ± 1.18 days vs. 2.69 ± 2.41 days, P = .048). The multivariate analysis revealed that LS (HR = 3.496, 95% CI = 1.108-11.030, P = .033), underweight (HR = 11.650, 95% CI = 2.155-62.990, P = .004), and lymphovascular invasion (HR = 3.123, 95% CI = 1.010-9.664, P = .048) were all predictive factors of PPM. For the pN + subgroup, the 3-year cumulative PPM rate was 29.6% in the LS group, significantly higher than 15.3% in the open group (P = .029), but there was no significant difference after PSM (P = .100).

Conclusion: LS offers faster postoperative recovery and comparable long-term survival outcomes. Therefore, it should remain a viable option for locally advanced T4 colon cancer. However, it is crucial to fully recognize the potential risk of increased PPM associated with LS, especially in patients with preoperative suspicion of positive lymph nodes. Further multicenter prospective studies are necessary to validate the potential risks of LS and gain insight into treatment efficacy in different patient populations. In addition, future studies should assess prognosis based on the grade and extent of peritoneal dissemination to provide a more nuanced understanding.