Comparison of Oncologic Outcomes after Mesocolic Resection in Right- and Left-Sided Colon Cancer.

CONTEXT Colorectal cancer represents the third leading cause of cancer-related mortality worldwide. Emerging evidence suggests distinct biological differences between right-sided colon cancer (RCC) and left-sided colon cancer (LCC), although their prognostic significance remains controversial.

AIMS To compare clinicopathological features and oncological outcomes between RCC and LCC following mesocolic resection and to identify independent prognostic factors.

SETTING AND DESIGN A retrospective cohort study was conducted at a tertiary center between January 2010 and December 2020.

METHODS AND MATERIALS A total of 948 patients with colon adenocarcinoma underwent curative resection and were categorized as RCC (n = 335) or LCC (n = 613), with analysis of demographic, pathological, and survival data focusing on overall survival and disease-free survival endpoints.

STATISTICAL ANALYSIS USED Continuous variables were compared using t-test or Mann-Whitney U test. Categorical variables were analyzed using Chi-square or Fisher's exact test. Univariate and multivariate Cox regression was performed to identify prognostic factors.

RESULTS RCC patients were older (62.6 ± 14.8 vs 59.3 ± 14.4 years, P < 0.001) and more frequently female (48.1% vs 37.0%, P < 0.001). RCC tumors showed more aggressive characteristics: poor differentiation (15.8% vs 7.7%), advanced T-stage (97.6% vs 83.9%), and higher KRAS mutations (53.4% vs 37.4%) (all P < 0.001). At median follow-up of 78.4 months, RCC demonstrated inferior survival with OS 79.1% vs 85.0% (P = 0.031) and DFS 74.0% vs 78.0% (P = 0.042). Multivariate analysis confirmed right-sided location as an independent adverse prognostic factor (Hazard Ratio = 1.45, 95% Confidence Interval: 1.05-2.01, P = 0.024).

CONCLUSIONS RCC showed more aggressive features and worse survival than LCC, suggesting tumor sidedness as an independent prognostic factor.