Outcomes of adjuvant capecitabine therapy in high-risk stage II colon cancer: A single-center analysis from Vietnam

Abstract

The optimal adjuvant chemotherapy for high-risk Stage II colon cancer remains debated. In Vietnam, capecitabine monotherapy is often chosen for its convenience and tolerability. In this retrospective study, 96 high-risk Stage II (pT3-4,N0,M0)patients underwent R0 resection at Vietnam National Cancer Hospital (2016 – 2019) and received capecitabine (1,250 mg/m² twice daily on days 1 – 14 of a 21-day cycle) for eight cycles. After a median follow-up of 60.6 months (range: 22 – 79), 5-year disease-free survival (DFS) was 89.5% and overall survival (OS) was 91.1%. In multivariate Cox analysis, lymphovascular/perineural invasion independently predicted poorer 5-year DFS (HR = 5.21; 95% CI: 1.02 – 26.55; p = 0.047), while both pathologic Stage IIC (pT4b) (HR = 6.98; 95% CI: 0.88 – 55.06; p = 0.009) and lymphovascular/perineural invasion (HR = 5.21; 95% CI: 1.02 – 26.55; p = 0.027) were independent predictors of worse 5-year OS. Grade ≥ 3 toxicities were uncommon: hand–foot syndrome (5.2%), diarrhea (2.1%), and hematologic events (4.2%); three patients (3.1%) discontinued therapy due to adverse events.These findings indicate that adjuvant capecitabine provides favorable 5-year DFS and OS in high-risk Stage II colon cancer. Patients with lymphovascular/perineural invasion or pT4b status may benefit from intensified approaches.