A first case report of clinical response to targeted therapy in a patient with primary myoepithelial carcinoma of the lung harboring EGFR exon 19 deletion.

Primary myoepithelial carcinoma of the lung is a rare subtype in lung cancer. Comprehensive molecular profiling of myoepithelial carcinoma of the lung is absent, neither was clinical evidence of targeted therapy available for this disease. Therefore, the optimal treatment regimen of this tumor needs to be established. Here we present a case of a 68-year-old patient with stage IVB primary myoepithelial carcinoma of the lung who harbored EGFR exon 19 deletion and KRAS mutation and underwent icotinib targeted therapy, achieving partial response (PR) with progression free survival (PFS) of 3 months. To our knowledge, this study describes the first documented case of primary myoepithelial carcinoma lung cancer patient harboring EGFR exon 19 deletion and KRAS mutation, and showed clinical efficacy of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI) treatment in this patient.