EP835 - Laproscopic Versus Open Surgery For T4 Colon Cancer: Oncologic And Perioperative Outcome

Purpose/Background: The role of laparoscopic surgery in T4 colon cancer remains debated due to concerns regarding technical feasibility and oncologic adequacy. Although minimally invasive techniques offer advantages such as faster recovery and reduced postoperative morbidity, their safety and efficacy in locally advanced tumors invading adjacent structures are uncertain. This study aimed to compare perioperative and long-term oncologic outcomes between laparoscopic and open resections for T4 colon cancer.

Methods/Interventions: A retrospective cohort study was conducted in King Chulalongkorn Memorial Hospital, a tertiary care referral center. Patients with pathologically confirmed pT4 colon cancer underwent curative-intent resection between January 2015 and December 2024 are included in the analysis. Patients who received neoadjuvant chemotherapy were excluded. Clinical data, including demographic characteristics, perioperative outcomes, and long-term oncologic results were analyzed and compared between laparoscopic and open groups. Unpaired t-tests and chi-square tests were used for univariate comparisons, while multivariable linear, logistic, and Cox regression models-adjusted for age, sex, stage, pathological T stage, and number of invaded organs were applied to evaluate continuous, categorical, and time-to-event outcomes, respectively.

Results/Outcomes: A total of 212 patients were included in the analysis, comprising 71 and 141 patients who underwent open and laparoscopic surgery, respectively. Baseline characteristics were comparable between groups. The laparoscopic cohort had a slightly higher mean age and body mass index.

A higher proportion of T4b lesions and multiorgan invasion were observed in the open surgery group (78.9 vs 34.0%, and 83.6 vs 40.5%, respectively; both p < 0.001). Stage III disease predominated in both groups but was more frequent in the laparoscopic cohort (54.6 vs 36.6%, p = 0.001). Tumor locations were mainly in the sigmoid and rectosigmoid colon (56.7 to 67.6 %) while rates of liver metastasis and peritoneal seeding were similar. Perioperative outcomes favored the laparoscopic approach. After multivariable adjustment, laparoscopic surgery was associated with significantly reduced intraoperative blood loss (−223 mL, p = 0.005) and shorter length of hospital stay (−3.5 days, p = 0.001). Operative time, lymph node yield, R0 resection rate, interval to adjuvant chemotherapy, postoperative complications, and readmission rates did not differ significantly between groups. Regarding long-term oncologic outcomes, the median follow-up period was 3.69 years. Five-year overall survival was comparable between the laparoscopic and open surgery (70.7 vs 68.3%, p=0.75). On multivariable Cox regression, laparoscopic resection demonstrated a significant survival advantage (HR = 0.46; p = 0.02), while recurrence rates were comparable between groups (HR = 0.87, p = 0.65).

Conclusion/Discussion: Laparoscopic resection for T4 colon cancer is feasible and oncologically safe in appropriately selected patients. Compared with open surgery, the laparoscopic approach yielded significantly lower blood loss, shorter hospitalization, and superior long-term survival, without compromising margin status or recurrence risk. These findings support laparoscopy as a viable curative-intent option for locally advanced colon cancer when performed in experienced centers with multidisciplinary expertise.

Clinical outcome
Table 1
Kaplan-Meier of overall survival (OS) and recurrence free survival (RFS )
Picture 1