A Prospective Exploratory Clinical Study of Metronomic Capecitabine as Adjuvant Therapy in Locoregionally Advanced Hypopharyngeal Carcinoma

Inclusion Criteria: * 1\. Age between 18 and 65 years old. 2. Histologically confirmed hypopharyngeal carcinoma, staged as IV (T4N0-1M0，anyTN2-3M0) (as defined by the 8th AJCC edition), Complete the recommended standard treatment (curative chemoradiotherapy, or radical surgery + postoperative chemo/radiotherapy ). 3\. No clinical evidence of persistent locoregional disease or distant metastases after definitive chemoradiotherapy. 4\. Within 8 weeks after completion of the last radiation dose. 5. Performance status of ECOG grade 0 or 1. 6. Adequate hematologic (neutrophil count \> 1.5×10\^9/L, hemoglobin \> 90g/L and platelet count \> 100×10\^9 /L), hepatic (alanine aminotransferase, aspartate aminotransferase ≤ 1.5×ULN, bilirubin ≤ 1.5×ULN, alkaline phosphatase \< 2.5×ULN) and renal function (creatinine clearance \> 50 ml/min). 7\. Patients must be appraised of the investigational nature of the study and provide written informed consent. Exclusion Criteria: * 1.Patients who were known to be intolerable or allergic to capecitabine. 2. Prior malignancy except adequately treated basal cell or squamous cell skin cancer, in situ cervical cancer. 3\. Any severe intercurrent disease, which may bring unacceptable risk or affect the compliance of the trial, for example, unstable cardiac disease requiring treatment, renal disease, chronic hepatitis, diabetes with poor control). 4\. With esophagus cancer. 5. Pregnancy or lactation. 6. Other conditions that are not eligible for enrollment.