Preoperative Chemoradiotherapy with Tegafur-Uracil, Capecitabine, or 5-Fluorouracil/Leucovorin for Rectal Cancer in an Asian Cohort: A Real-World Comparison from the Pre-TNT Era

Preoperative concurrent chemoradiotherapy (CCRT) is an important treatment for locally advanced rectal cancer, but the choice of chemotherapy utilized with radiotherapy is inconsistent. Guidelines mainly recommend 5-fluorouracil/leucovorin (5-FU/LV) or capecitabine, whereas tegafur-uracil (UFT) is widely used in Asia with limited comparative data. We evaluated UFT versus capecitabine and 5-FU/LV in an Asian real-world cohort. Between 2012 and 2019, 79 patients with biopsy-proven cT2-4N0-N2 rectal cancer received pelvic radiotherapy plus concurrent UFT (n = 31), capecitabine (n = 30), or 5-FU/LV (n = 18), followed by surgery. Endpoints included acute toxicity, pathologic complete response (pCR), T/N downstaging, overall survival (OS), and recurrence-free survival (RFS). Diarrhea was the most common toxicity (grade 1-2 in 68.4%). Neutropenia differed by regimen (UFT, 0%; capecitabine, 20.0%; 5-FU/LV, 16.7%), with one grade 3 event (5-FU/LV). The overall pCR rate was 17.7% (UFT, 16.1%; capecitabine, 23.3%; 5-FU/LV, 11.1%), and nodal downstaging was more frequent with capecitabine. After a median follow-up of 39.1 months, the 3-year OS and RFS were 88.9% and 68.9%, respectively, without significant survival differences among regimens. UFT-based long-course CCRT appears feasible and generally tolerable in routine Asian practice, with no clear signal of substantially worse pCR or survival outcomes in this retrospective cohort. These real-world data can inform individualized regimen selection.