Adjuvant Chemotherapy Duration and Disease-Free Survival in Low-Risk Stage III Colon Cancer with N1a-b and N1c Disease: Insights from a Single-Center Retrospective Analysis


KARAOĞLAN B. B., Ozturk I., AKYOL C., SAVAŞ B., UTKAN G.

JOURNAL OF GASTROINTESTINAL CANCER, cilt.56, sa.1, 2025 (ESCI) identifier identifier identifier

Özet

Background Tumor deposits (TDs) are known to have a poor prognosis independent of lymph node (LN) involvement and are considered equivalent to LN metastases in the latest staging system. In stage III colon cancer (CC), high-risk patients (pT4 or pN2) receive 6 months of adjuvant chemotherapy, while low-risk patients (pT1-3 and N1) are recommended either 3 or 6 months of CAPOX or 6 months of FOLFOX therapy. However, the optimal chemotherapy duration for low-risk patients classified as pN1c remains unknown. The aim of this study is to investigate the impact of adjuvant chemotherapy duration (3 months vs. 6 months) on survival in patients with low-risk stage III CC either in pN1a-b and pN1c patient groups. Methods We retrospectively analyzed patients with stage III CC who underwent surgery at a tertiary center between January 2014 and May 2024. Demographic and pathological data of patients were retrospectively collected. The primary outcome was disease-free survival (DFS). Results A total of 142 patients were included. Among the patients, 116 were pT1-3N1a-b and 26 were pT1-3N1c. Local (23.1% vs. 1.7%, P < 0.001) and overall (38.5% vs 14.6%, P = 0.011) recurrences were significantly higher in the pN1c group. Univariate and multivariate analyses revealed no significant impact of adjuvant chemotherapy duration on DFS in the pN1a-b group (P = 0.359), whereas in the pN1c group, 3-month chemotherapy resulted in significantly shorter DFS (P = 0.044) in univariate analysis. Conclusion Our study indicates that shorter duration of adjuvant chemotherapy is associated with worse survival and 6-month chemotherapy is recommended for patients with pT1-3 and N1c disease.