EP551 - Histopathological Features and Prognostic Significance of High-Risk Stage II Colon Adenocarcinomas versus Stage III Disease

Sunday, May 11, 2025

4:22 PM – 4:27 PM PT

Location: Monitor 2, Sails Pavilion, Upper Level

ePoster Presenter(s)

Ergin Erginoz, MD

Department of General Surgery
Istanbul University Cerrahpasa - Cerrahpasa School of Medicine
Istanbul, Istanbul, Turkey

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

Author(s)

MF

Muratcan Firat, MD

Department of General Surgery
Istanbul University Cerrahpasa - Cerrahpasa School of Medicine
Istanbul, Istanbul, Turkey

Disclosure information not submitted.
KS

Kevser Sak, MD

Deparment of Public Health
Dulkadiroglu District Health Directorate
Istanbul, Istanbul, Turkey

Disclosure information not submitted.
SE

Sefa Ergun, MD

Department of General Surgery
Istanbul University Cerrahpasa - Cerrahpasa School of Medicine
Istanbul, Istanbul, Turkey

Disclosure information not submitted.
SU

Server Sezgin Uludag, MD

Department of General Surgery
Istanbul University Cerrahpasa - Cerrahpasa School of Medicine
Istanbul, Istanbul, Turkey

Disclosure information not submitted.
SD

Suleyman Demiryas, MD

Department of General Surgery
Istanbul University Cerrahpasa - Cerrahpasa School of Medicine
Istanbul, Istanbul, Turkey

Disclosure information not submitted.
KZ

Kagan Zengin, MD

Department of General Surgery
Istanbul University Cerrahpasa - Cerrahpasa School of Medicine
Istanbul, Istanbul, Turkey

Disclosure information not submitted.
SB

Sebnem Batur, MD

Department of Pathology
Istanbul University Cerrahpasa - Cerrahpasa School of Medicine
Istanbul, Istanbul, Turkey

Disclosure information not submitted.
NK

Nuray Kepil, MD

Department of Pathology
Istanbul University Cerrahpasa - Cerrahpasa School of Medicine
Istanbul, Istanbul, Turkey

Disclosure information not submitted.

Senior Author(s)

MC

Mehmet Sinan Carkman, MD

Department of General Surgery
Istanbul University Cerrahpasa - Cerrahpasa School of Medicine
Istanbul, Istanbul, Turkey

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

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

Ergin Erginoz, MD: This individual has no financial relationships with ineligible companies.

Mehmet Sinan Carkman, MD: This individual has no financial relationships with ineligible companies.

Image or Table (Do Not add text here):

Purpose/Background: The clinicopathologic characteristics that are associated with an increased risk of colon cancer recurrence and mortality are referred to as high risk features (HRF). According to the National Comprehensive Cancer Network guidelines, the HRFs include poorly or undifferentiated tumors, lymphovascular invasion, perineural invasion, bowel obstruction or perforation, inadequate lymphadenectomy ( < 12 lymph nodes), T4 disease, and histologically positive margins. In this study, we hypothesized that stage II tumors with ≥3 HRFs would have a worse impact on survival compared to stage III disease.

Methods/Interventions: A retrospective chart review was completed for 377 consecutive patients diagnosed with stage II and III colon adenocarcinoma between 2016 and 2020 in a single institution. Patients were grouped into three groups as stage II ( < 3 HRFs), stage II (≥3 HRFs), and stage III and the clinicopathological data was evaluated retrospectively.

Results/Outcomes: Patients with stage II disease ≥3 HRFs (n=88) tended to have higher lymphatic invasion (p < 0.001), plexus invasion (p=0.043), perineural invasion (p < 0.001), and 90-day mortality (p=0.026) compared to patients with stage III disease (n=187). Patients with stage III disease tended to have higher vascular invasion (p < 0.001) lower peritumoral Crohn’s-like lymphoid reaction (p < 0.001), higher preoperative CEA (p=0.001), and higher preoperative CA 19-9 (p=0.303). The five-year overall survival (OS) and disease-free survival (DFS) rates were 79.4% and 74.5% in patients with stage II < 3 HRF, 58.9% and 58.9% in patients with stage II ≥3 HRF, and 71.2% and 61.3% in patients with stage III disease (p=0.037 and p=0.040, respectively). In subgroup analysis, there was a significant difference between stage II < 3 HRF and stage II ≥3 HRF for OS (p=0.010) and DFS (p=0.017). However, there was not a statistically significant difference between stage II ≥3 HRF and stage III in terms of OS (p=0.126) and DFS (p=0.600). According to the factors affecting OS, age ≥ 65 years, colostomy formation, ≤11 harvested lymph nodes, and higher CEA were significant prognostic factors in the Cox proportional hazards multivariate analysis. According to the factors affecting DFS, age ≥ 65 years, colostomy formation, larger tumor volume, ≤11 harvested lymph nodes, higher CEA, and stage III disease were significant prognostic factors in multivariate analysis.

Conclusion/Discussion: Stage II colon adenocarcinomas with ≥3 HRFs displayed worse survival compared to stage II < 3 HRF and stage III disease in the statistical analysis. In subgroup analysis, no significant difference in survival was observed between stage II ≥3 HRF and stage III disease. This finding suggests that stage II colon cancer with ≥3 HRF could behave similarly to stage III disease and both of these subgroups could be managed similarly in the postoperative period, highlighting the need for further study in this specific group of patients.