We employed an independent dataset for validating the AST/ALT ratio as a prognostic factor in patients with HNSCC. In particular, we searched the cancer registry of the Osaka General Medical Center to identify patients with locoregionally advanced HNSCC who were treated between 2006 and 2012. We identified 189 consecutive patients with histologically confirmed SCC of the oropharynx, hypopharynx, larynx, and oral cavity. Among them, 22 patients were excluded because of a follow-up period of <24 months and insufficient clinical or laboratory data. The final number of patients for analysis was 167. The data of these patients were used to estimate survival rates and hazard ratios (HRs) according to the risk groups.