# Side-Specific Prognostic Factors in Colon Cancer: A Retrospective Analysis of Right- and Left-Sided Tumors

## TL;DR

This study finds that colon cancer tumors on the right and left sides have different prognostic factors, suggesting treatment should consider tumor location.

## Contribution

The study identifies side-specific prognostic factors in colon cancer, offering insights for personalized treatment strategies.

## Key findings

- Right-sided tumors were associated with older age, lower hemoglobin, and more anemia.
- Left-sided tumors showed higher rates of emergency surgery and metastases.
- AJCC stage was a strong predictor of survival in both tumor locations.

## Abstract

Colon cancer remains a significant global health challenge, with growing evidence that tumors originating on the right and left sides of the colon represent distinct disease entities. These differences include variations in patient characteristics, tumor biology, and survival outcomes. In this retrospective analysis of 247 patients, we compared clinicopathological features and prognostic factors between right- and left-sided tumors. Our findings demonstrate that tumor location is associated with measurable differences in prognosis, suggesting that side-specific factors should be considered when planning treatment strategies. This knowledge may contribute to more precise risk stratification and individualized management approaches in clinical practice.

Background: Tumor sidedness in colon cancer has been linked to biological and clinical differences, but its impact on survival and prognostic factors remains unclear. This study aimed to find the predictors of overall survival (OS) in patients with right-sided colon cancer (RCC) and left-sided colon cancer (LCC) undergoing surgical treatment. Methods: A retrospective single-center study was conducted on 247 patients with colon cancer, including 117 with RCC and 130 with LCC. Clinical, surgical, and pathological variables were analyzed. Cox regression and ROC curve analyses were used to identify independent predictors of OS in the overall cohort and tumor-side subgroups. Results: RCC patients were older (69 vs. 68 years, p = 0.03), had lower hemoglobin levels (11.7 vs. 12.95 g/dL, p < 0.01), and more often presented with anemia (34.18% vs. 11.48%, p < 0.001). LCC patients more frequently underwent emergency surgery (13.74% vs. 5.69%, p = 0.03). Mucinous adenocarcinomas were more frequent in RCC (12.82% vs. 5.38%, p = 0.03), whereas distant metastases (15.38% vs. 6.84%, p = 0.03) and liver metastases (14.61% vs. 6.84%, p = 0.04) were more common in LCC. The one-year overall survival was similar between LCC and RCC before (88.09% vs. 91.52%, p = 0.15) and after propensity score matching (89.32% vs. 91.87%, p = 0.60) In multivariate Cox regression, independent predictors of lower OS included advanced AJCC stage (HR = 34.54, p < 0.001) in RCC, while, in LCC, AJCC stage (HR = 31.14, p = 0.001 and stoma (HR = 5.86, p = 0.01) were significant. Tumor location itself was not associated with OS (p = 0.18). Conclusions: Prognostic factors in colon cancer vary with tumor location. Side-specific risk stratification may improve outcome prediction and guide personalized management.