The EGFR and downstream signaling pathways play an important role in tumorigenesis in oral squamous cell carcinoma (OSCC). Gene copy number alteration is one mechanism for overexpressing the EGFR protein and was also demonstrated to be related to lymph node metastasis, tumor invasiveness and perineural invasion. | EGFR copy number alterations in primary tumors metastatic lymph nodes and recurrent and multiple primary tumors in oral cavity squamous cell carcinoma