Although the possible reason of the significant association between EGFR overexpression and tumor recurrence needs to be investigated in more detail, the constitutive activation of EGFR by gene mutations and/or amplification has been shown to be related to initiation, progression, and poor prognosis in several cancers, including non-small cell lung cancer (NSCLC), colorectal cancer (CRC), squamous cell carcinoma of the head and neck (SCCHN), and glioblastoma (18, 19). Here, EGFR is linked to head and neck squamous cell carcinoma.