A Phase II Study of Adjuvant Chemotherapy of Tegafur-Uracil for Patients with Breast Cancer with HER2-negative Pathologic Residual Invasive Disease After Neoadjuvant Chemotherapy.

BACKGROUND: There is no consensus on the need for adjuvant chemotherapy for patients with pathological residual invasive breast cancer (non-pCR) after neoadjuvant chemotherapy (NAC). We evaluated the tolerability and safety of tegafur-uracil (UFT) as adjuvant chemotherapy for patients with human epidermal growth factor receptor 2-negative breast cancer that resulted in non-pCR after NAC. PATIENTS AND METHODS: We treated patients with 270 mg/m2 UFT per day for 2 years after definitive surgery and radiotherapy, if necessary. In cases with hormone-sensitive cancer, patients received concurrent endocrine therapy. The primary end-point was the rate of completion of scheduled UFT therapy. Secondary end-points included safety and disease-free survival. RESULTS: Twenty-one out of 29 patients (72%) completed the scheduled therapy. Eight patients discontinued the study treatment because of disease recurrence, toxicities, and patients' wish. Excluding liver dysfunction, adverse events were quite mild. CONCLUSION: Adjuvant UFT therapy after NAC was feasible and safe.