title: Pulmonary sclerosing hemangioma presenting with dense spindle stroma cells: a potential diagnostic pitfall.
abstract: Pulmonary sclerosing hemangioma (PSH) is an uncommon pulmonary tumor. Histologically, PSH typically consists of two types of cells, surface cuboidal cells and polygonal cells, four architectural patterns including papillary, sclerotic, solid, and hemorrhagic. Herein, we present a case of PSH in a 59-year-old Chinese female. The tumor was predominantly composed of solid area presenting with diffuse spindle cells rather than polygonal cells. Focally, classical papillary and sclerotic area could be seen. Immunohistochemical staining showed that the spindle cells were positive for TTF-1, EMA, Actin(SM) and Vimentin, and negative for cytokeratin, cytokeratin7, cytokeratin5/6, surfactant apoprotein A, surfactant apoprotein B, CD34, CD99, S-100, HMB45, Desmin, Synaptophysin, CD56, ALK and Calretinin. The immunophenotype of the dense spindle cells in this case was similar to that of the polygonal cells, and thus the spindle cells may be the variants of polygonal cells. Based on morphologic features and the immunohistochemical profile, the tumor was diagnosed as a PSH. The significance of spindle cells change is unclear for us. To our knowledge, this is the first reported case of PSH showing dense spindle cells in solid area. This case represents a potential diagnostic pitfall, as it may be misdiagnosed as a mesenchymal tumor such as inflammatory myofibroblastic tumor, synovial sarcoma, solitary fibrous tumor, leiomyoma, or even mesothelioma, especially if the specimen is limited or from fine- needle aspiration.
  The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1235401622806126.
authors.affiliation: Department of Pathology, the First Affiliated Hospital and College of Basic Medical Sciences, China Medical University, Shenyang 110001, China.
authors.forename: Xu-Yong
authors.initials: XY
authors.lastname: Lin
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Chui-Feng
authors.initials: CF
authors.lastname: Fan
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Juan-Han
authors.initials: JH
authors.lastname: Yu
authors.forename: Shun-Dong
authors.initials: SD
authors.lastname: Dai
authors.forename: Liang
authors.initials: L
authors.lastname: Wang
authors.forename: En-Hua
authors.initials: EH
authors.lastname: Wang
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D008197:Lymph Node Excision; D008875:Middle Aged; D011013:Pneumonectomy; D011237:Predictive Value of Tests; D047868:Pulmonary Sclerosing Hemangioma / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D003074:Solitary Pulmonary Nodule / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D017154:Stromal Cells / Q000737:chemistry / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor