A clinical study of gene expression models for predicting response to S-1 in patients with head and neck squamous cell carcinoma

INTERVENTION: Collect primary tumor and corresponding normal tissue specimens from patients enrolled in this study. CONDITION: Patients who are suitable for S‐1 chemotherapy as a first‐line treatment in head and neck squamous cell carcinoma. PRIMARY OUTCOME: Tumor response SECONDARY OUTCOME: Progression‐free and overall survival INCLUSION CRITERIA: 1. Primary squamous cell carcinoma of head and neck 2. New or recurrent case 3. Enable sampling of primary tumor 4. Have evaluable tumor region 5. No previous history of chemotherapy nor radiotherapy 6. Not treated with combined radiotherapy or other anticancer drugs 7. An Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2 8. Adequate organ functions; white blood cell count or WBC, >3,500/mm3, <12,000/mm3; platelet count or Plt, >100,000/mm3; neutrophil count or Neu, >2000/mm3; hemoglobin or Hb >9.0g/dl; total serum bilirubin, 1.5 times of normal range in each institute; aspartate aminotransaminase or AST and alanine aminotransaminase or ALT, 2.5 times of normal range in each institute; creatinine clearance or CCr (or e‐GFR), >80ml/minute 9. Adult patients aged 20 years or older 10. Written informed consent obtained