Adjuvant Tegafur-Uracil Improves Survival in Low-Risk, Mismatch Repair Proficient Stage IIA Colon Cancer: A Propensity Score-Matched Analysis.

Background: The benefit of adjuvant chemotherapy for low-risk, mismatch repair proficient (pMMR) stage IIA colon cancer is uncertain. Surveillance is standard, but some patients relapse. Tegafur-uracil (UFT) is a low-toxicity oral option that may offer benefit; Methods: This retrospective study included patients with resected low-risk, pMMR stage IIA colon cancer (2013-2022). Patients receiving ≥5 postoperative UFT prescriptions were compared with those under surveillance. Propensity score matching (1:1) was applied, and disease-free survival (DFS) and overall survival (OS) were analyzed using Kaplan-Meier and Cox models with sensitivity analyses.; Results: Among 279 eligible patients, 71 matched pairs were analyzed. UFT reduced the risk of recurrence or death by 57% (DFS HR = 0.43, 95% CI 0.25-0.75, p = 0.002) and mortality by 62% (OS HR = 0.38, 95% CI 0.21-0.68, p < 0.001); Conclusions: UFT improved DFS and OS in low-risk pMMR stage IIA colon cancer, suggesting surveillance alone may undertreat some patients. Prospective trials are warranted.