EGFR and mucoepidermoid carcinoma: Differential diagnoses include mucoepidermoid carcinoma, lymphoepithelial carcinoma and submandibular metaplasia. There is an increased prevalence of nodal involvement in the PSCC, which justifies neck dissection (regions I, II and III of the neck). The RAS mutation leading to resistance to anti-EGFR therapies may be assessed.