Pulmonary Pleomorphic Carcinoma: A Clinicopathological Study Including EGFR Mutation Analysis

BackgroundPulmonary pleomorphic carcinoma is a rare epithelial tumor and has an aggressive clinical course. As few studies of pulmonary pleomorphic carcinoma have been described, the clinicopathological characteristics of the disease remain unclear. Especially, the information on the epidermal growth factor receptor (EGFR) mutation status of pulmonary pleomorphic carcinoma is sparse.MethodsWe retrospectively examined 17 patients with pulmonary pleomorphic carcinoma. EGFR mutation and Ki-67 labeling index were investigated in these patients.ResultsThe median age of the patients was 72 years (range, 47–84 years). Thirteen patients were men and four were women. EGFR mutation was observed in 3 (18%) of 17 patients. The median value of Ki-67 labeling index was 62% (range, 20–87%). Positron emission tomography with 18-fluorodeoxy-glucose was performed in 16 patients, and the standardized uptake value tended to be high (median 19.3). The survival of patients without surgery demonstrated a significantly poor prognosis compared with those with surgery (P = 0.0096). Palliative chemotherapy was almost poor response in advanced pulmonary pleomorphic carcinoma. The response to gefitinib in a patient with EGFR mutation was small and transient.ConclusionEGFR mutation was recognized in approximately 20% of patients with pulmonary pleomorphic carcinoma. It is necessary to investigate whether the use of a molecular targeting drug improves outcome for pulmonary pleomorphic carcinoma.