To evaluate the efficacy of GM-CSF to preventing oral mucositis for patients with nasopharyngeal carcinoma receiving radiotherapy.

Patients of GM-CSF group receive GM-CSF washmouth four times a day during radiotherapy. Control arm receive conventioanl care during radiotherapy. Visual signs of radiation or chemotherapy-induced mucosal damage were independently assessed during the course of RT by a radiation oncologist or other trained study personnel. The incidence of severe oral mucositis, the severe oral mucositis last time, quality of life between the two arms would be calculated.

Inclusion Criteria:

• a. Patients with histologically confirmed non-keratinizing nasopharyngeal carcinoma (including differentiated type and undifferentiated type, world health organization [WHO] II or III).

  b. Original clinical staged as II-IVa (according to the 8 th AJCC edition) c. Male or female who are not pregnant. d. No evidence of distant metastasis (M0). e. Age between 18-65 years. f. WBC≥4×109/L, PLT≥100×109/L, HGB≥90g/L. g. 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.

  i. With normal renal function test (creatinine clearance rate≥60 ml/min or creatinine< 1.5×ULN.

  j. The Eastern Cooperative Oncology Group (ECOG) Performance status less or equal to 1.

  k. Patients must be informed of the investigational nature of this study and give written informed consent.

  l. Patients receive induction chemotherapy plus concurrent chemoradiotherpy or concurrent chemoradiotherapy, or radiotherapy alone.

Exclusion Criteria:

• Age <18 or >65years. c. With clinical stage of I or IVb (according to the 8 th AJCC edition). d. Patients with tumor recurrence or distant metastasis. e. Prior malignancy except adequately treated basal cell or squamous cell skin cancer, in situ cervical cancer.

  f. History of previous radiotherapy (except for non-melanomatous skin cancers outside intended RT treatment volume).

  g. Prior chemotherapy or surgery (except diagnostic) to primary tumor or nodes.

  h. Pregnancy or lactation (consider pregnancy test in women of child-bearing age and emphasize effective contraception during the treatment period).

  i. Any severe intercurrent disease, which may bring unacceptable risk or affect the compliance of the trial, for example, unstable cardiac disease requiring treatment, acute exacerbation of chronic obstructive pulmonary disease or other respiratory illness requiring admission to hospital, renal disease, chronic hepatitis, diabetes with poor control (fasting plasma glucose >1.5×ULN), and mental disturbance.