title: Pulmonary myxoid leiomyosarcoma.
abstract: A primary myxoid leiomyosarcoma arising from the peripheral bronchus of the right middle lobe was removed from a 20 year old man and examined by immunohistochemistry and electron microscopy. The tumor was well circumscribed, yellow-whitish focal polypoid growth into the bronchial lumen and consisted of spindle cells with abundant myxoid substance in the stroma. Intrapulmonary metastasis, invasion to the bronchial wall and a few mitotic figures were found. Immunohistochemically, several, but not all, tumor cells were positive against anti-vimentin, anti-S-100 protein, anti-myosin and anti-muscle specific actin. Ultrastructurally, tumor cells had thin filaments with dense bodies, pinocytic vesicles and discontinuous basal lamina. These findings indicate a myoxoid variant of leiomyosarcoma arising from mesenchyme in the peribronchial area.
authors.affiliation: Second Department of Pathology, Niigata University School of Medicine, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Koizumi
authors.forename: T
authors.initials: T
authors.lastname: Fukuda
authors.forename: Y
authors.initials: Y
authors.lastname: Ohnishi
authors.forename: M
authors.initials: M
authors.lastname: Naito
authors.forename: I
authors.initials: I
authors.lastname: Emura
authors.forename: K
authors.initials: K
authors.lastname: Sato
authors.forename: T
authors.initials: T
authors.lastname: Hirono
authors.forename: E
authors.initials: E
authors.lastname: Suzuki
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D006801:Humans; D007150:Immunohistochemistry; D007890:Leiomyosarcoma / Q000473:pathology* / Q000648:ultrastructure; D008175:Lung Neoplasms / Q000473:pathology* / Q000648:ultrastructure; D008297:Male