Postoperative Concurrent Chemoradiation for Head and Neck Cancer With Multiple Minor Risk

Inclusion Criteria: * Primary squamous cell carcinoma of head and neck, after tumor excision and neck dissection, pathology has confirmed three or more of the following adverse prognostic factors, including: 1. Marginale surgery but a safe distance from the residual tumor ≦ 4mm. 2. The tumor is located in the hard palate or the retromolar region. 3. Poorly differentiated cell type. 4. Tumor invasion to the nerve. 5. Tumor invasion to lymphatic vessels. 6. Tumor invasion to the small blood vessels. 7. Tumor invasion to the bone. 8. Tumor invasion to the skin. 9. Depth of tumor invasion ≧ 10mm. 10. Occurred in single lymph node metastasis. Exclusion Criteria: * No or presence of adverse prognostic factor but less than 2. * Presence of either one conditions listed here: positive resection margin, resection margin negative but less than 1 mm, pathologic N2 or N2, or presence of nodal metastasis with extracapsular spreading. * ECOG performance status \> 2. * Previous cancer history (except basal cell or squamous cell skin cancer) or other synchronous malignant disease. * Women during pregnancy.