Correlation of these 18 (including ELF3) co-occurring HIDDEN cell biomarkers with patient survival could not be analyzed in the HNSCC patient cohort due to the high variance in ELF3 expression across anatomical sites (Fig. 7d), with each anatomical site having either predominately HPV+ or HPV− tumors. Here, ELF3 is linked to head and neck squamous cell carcinoma.