ALDH2 Mutation in Taiwanese Head and Neck Cancer

* One-site audit. The enrolled subject is confirmed by PIs ◦◦Source data is compared to external data sources medical records, either paper or electronic case report forms. * NCI CTCAE v5.0 for AE records * Patient recruitment according to inclusion criteria: 1. Newly diagnosed locally head and neck squamous cell carcinoma; 2. Apply for primary chemoradiation or adjuvant chemoradiation; 3. Signed informed consent * Sample size assessment: 60 subjects will be included in one year for total 120 subjects * Missing data to address situations where variables are reported as missing, unavailable, "non-reported," uninterpretable, or considered missing because of data inconsistency or out-of-range results * Fisher's exact test is for category comparison. Kaplan-Meier analysis is for survival analysis. AE grades will be analyzed according to NCI guideline. Two-side p \< 0.05 is suggested significant.