title: A true pulmonary carcinosarcoma that required diagnostic differentiation from a pleomorphic adenoma: a case report.
abstract: Pulmonary carcinosarcoma is a rarely encountered tumor. We treated a patient who had an intrabronchial polypoid lesion that required a diagnostic differentiation from epithelial-mesenchymal mixed neoplasms inclusive of pleomorphic adenoma, and that was diagnosed by immunohistochemical staining to be a true carcinosarcoma. A 69-year-old man underwent left pneumonectomy in November 2000 with a diagnosis of atelectasis resulting from a tumor obstructing the left lower lobar bronchus, and also a lung abscess. The tumor was initially diagnosed as pleomorphic adenoma, since it contained both benign-looking epithelial and mesenchymal elements, but immunohistochemical staining demonstrated myoglobin-positive rhabdomyosarcomatous elements along with cytokeratin-positive squamous cell carcinoma elements. A definite diagnosis of pulmonary carcinosarcoma was confirmed.
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Nippon Medical School, Tokyo, Japan.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Yoshino
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Kubokura
authors.forename: Shigeo
authors.initials: S
authors.lastname: Yamauchi
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Ohaki
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Koizumi
authors.forename: Kazuo
authors.initials: K
authors.lastname: Shimizu
mesh_terms: D008949:Adenoma, Pleomorphic / Q000473:pathology*; D000368:Aged; D001999:Bronchoscopy; D002296:Carcinosarcoma / Q000150:complications / Q000473:pathology* / Q000601:surgery; D003937:Diagnosis, Differential; D006801:Humans; D007150:Immunohistochemistry; D008169:Lung Abscess / Q000209:etiology / Q000473:pathology; D008175:Lung Neoplasms / Q000150:complications / Q000473:pathology* / Q000601:surgery; D008297:Male; D011013:Pneumonectomy; D001261:Pulmonary Atelectasis / Q000209:etiology / Q000473:pathology; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome