Concurrent Chemotherapy in Intermediate Risk Patients Treated With Intensity-modulated Radiotherapy

Inclusion Criteria: Patients with newly histologically confirmed non-keratinizing (according to WHO histologically type). Tumor staged as T1-2N1/T2-3N0(according to the 7th AJCC edition). No evidence of distant metastasis (M0). Satisfactory performance status: Karnofsky scale (KPS) ≥ 70. Adequate marrow: leucocyte count ≥ 4000/μL, hemoglobin ≥ 90g/L and platelet count ≥ 100000/μL. Normal liver function test: Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST) \< 1.5×upper limit of normal (ULN) concomitant with alkaline phosphatase (ALP) ≤ 2.5×ULN, and bilirubin ≤ ULN. Adequate renal function: creatinine clearance ≥ 60 ml/min. Patients must be informed of the investigational nature of this study and give written informed consent. Exclusion Criteria: Neck lymph node with extracapsular spread. Maximal axial diameter of neck lymph node ≥30mm, positive neck lymph node at level IV and/or Vb. Pretherapy plasma EBV DNA level ≥4000 copy/ml. WHO Type keratinizing squamous cell carcinoma or basaloid squamous cell carcinoma. Age \> 70 or \< 18. Treatment with palliative intent. Prior malignancy except adequately treated basal cell or squamous cell skin cancer, in situ cervical cancer. Pregnancy or lactation (consider pregnancy test in women of child-bearing age and emphasize effective contraception during the treatment period). History of previous RT (except for non-melanomatous skin cancers outside intended RT treatment volume). Prior chemotherapy or surgery (except diagnostic) to primary tumor or nodes. 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 (fasting plasma glucose \> 1.5×ULN), and emotional disturbance.