EP557 - Comparative Analysis of Left and Right-Sided Metastatic Colon Adenocarcinoma: A SEER Database Study

Sunday, May 11, 2025

4:06 PM – 4:11 PM PT

ePoster Presenter(s)

Zoe Garoufalia, MD (she/her/hers)

Colorectal Surgery Fellow
Cleveland Clinic Florida
Cleveland Clinic Florida
Weston, FL, United States

All of the relevant financial relationships listed below have been mitigated.
This individual has no financial relationships with ineligible companies.

Author(s)

Sameh H. Emile, MBBCh, MSc, MD, FACS

Project Scientist
Cleveland Clinic Florida
Cleveland Clinic Florida
Plantation , FL, United States

All of the relevant financial relationships listed below have been mitigated.
This individual has no relevant relationships with ineligible companies.
RG

Rachel Gefen, MD

Surgeon
Cleveland Clinic Florida
Weston, Florida, United States

Disclosure information not submitted.
Marylise Boutros, MD (she/her/hers)

Colorectal Surgeon
Cleveland Clinic Florida
McGill University
Weston, Florida, United States

All of the relevant financial relationships listed below have been mitigated.
This individual has no relevant relationships with ineligible companies.
Nir Horesh, MD

Resident Physician
Cleveland Clinic Florida
Cleveland Clinic Florida
Weston, FL, United States

All of the relevant financial relationships listed below have been mitigated.
This individual has no financial relationships with ineligible companies.
Justin Dourado, MD (he/him/his)

General Surgery Residency
Cleveland Clinic Florida
Florida Atlantic University
Weston, Florida, United States

Disclosure information not submitted.
ES

Ebram Salama, MD

Surgeon
Cleveland Clinic Florida
Weston, Florida, United States

Disclosure information not submitted.

Senior Author(s)

Steven D. Wexner, MD, PhD (Hon), MD, PhD (Hon), FACS, FRCS, FRCSI, MAMSE

Emeritus Chair, Department of Colorectal Surgery
Cleveland Clinic Florida
Cleveland Clinic Lerner College of Medicine at Case Western Reserve University
Weston, Florida, United States

All of the relevant financial relationships listed below have been mitigated.
This individual has no relevant relationships with ineligible companies.

All of the relevant financial relationships listed below have been mitigated.

Zoe Garoufalia, MD: This individual has no financial relationships with ineligible companies.

Sameh H. Emile, MBBCh, MSc, MD, FACS: This individual has no relevant relationships with ineligible companies.

Marylise Boutros, MD: This individual has no relevant relationships with ineligible companies.

Nir Horesh, MD: This individual has no financial relationships with ineligible companies.

Steven D. Wexner, MD, PhD (Hon), FACS, FRCS, FRCSI, MAMSE, MD, PhD (Hon): This individual has no relevant relationships with ineligible companies.

Image or Table (Do Not add text here):

Purpose/Background: The literature suggests that right-sided colon cancer has poorer prognosis than left-sided. The present study aimed to compare characteristics and outcomes of left and right-sided metastatic colon adenocarcinoma utilizing the SEER database.

Methods/Interventions: The National Cancer Institute’s SEER Research Data, Nov 2022 Submission Database was searched from 2010-2020 for patients with stage IV colon adenocarcinoma. The cohort was subdivided by tumor location (left or right; transverse was excluded). The 2 groups were compared for demographics, treatment, and extent of metastatic disease. Main outcomes were overall (OS) and cancer-specific survival (CSS).

Results/Outcomes: In a cohort of 39782 patients, those with right-sided metastatic colon cancer (20986) had a significantly higher proportion of poor differentiation (29.2% vs 18.8%, p< 0.001), mucinous (8.8% vs 5.1%, p< 0.001), and signet-ring cell (2.6% vs 1.3%, p< 0.001) histology. Patients with metastatic right-sided colon cancer in >1 distant organ, had a median OS of 7 months (95% CI: 6-8), significantly shorter than the left-sided group with similar metastatic burden (median survival: 15 months, 95% CI: 14-15). Stratification by specific secondary organ involvement demonstrated varying median survival times, with right-sided tumors consistently showing poorer prognosis across different metastatic sites. When adjusted for age, sex, race, chemotherapy, surgery, tumor histology and grade, right-sided tumor location was an independent predictor for worse OS (HR=1.17, p< 0.001) and CSS (HR= 1.19, p< 0.001).

Conclusion/Discussion: Patients with metastatic right colon cancer had worse prognosis than did patients with metastatic left-sided cancer, regardless of site and burden of metastases. Our findings highlight the need for tailored approaches based on tumor location.