title: Primary Pseudomyogenic Hemangioendothelioma of Bone.
abstract: Pseudomyogenic hemangioendothelioma (PMH) is a well-recognized neoplasm that usually arises in the soft tissue; concurrent bone involvement occurs in 24% of cases. PMH of bone without soft tissue involvement is rare. We describe the clinicopathologic findings of 10 such cases, the largest series reported to date. The study included 9 male and 1 female patient; their ages ranged from 12 to 74 years (mean 36.7 y). All patients had multiple tumors with a distinct regional distribution: 45% restricted to the lower extremity; 25% to the spine and pelvis; and 15% to the upper extremity. On imaging studies the tumors were well circumscribed and lytic. The neoplasms were composed of spindled cells arranged in intersecting fascicles with scattered epithelioid cells; epithelioid cells predominated in 3 cases. The neoplastic cells contained abundant densely eosinophilic cytoplasm and vesicular nuclei. There was limited cytologic atypia and necrosis, few mitoses (0 to 2/10 high-power fields), and inconspicuous stroma. Unique findings included abundant intratumoral reactive woven bone and hemorrhage with numerous osteoclast-like giant cells. Immunohistochemically, most tumors were positive for keratin, ERG, and CD31; CD34 was negative. The balanced t(7:19)(q22;13) translocation was documented in 3 cases. Follow-up is limited, but no patient developed documented visceral dissemination, and all have stable or progressive osseous disease. PMH exclusively involving bone is rare. It is multicentric, often involves the lower extremity, and has unusual morphology. The differential diagnosis includes epithelioid vascular neoplasms, giant cell tumor, bone forming neoplasms, and metastatic carcinoma. Because of its rarity, unusual presentation, and morphology, accurate diagnosis can be challenging.
authors.affiliation: *Department of Pathology, University of Miami Hospital, Miami, FL §Mayo Clinic, Rochester, MN ¶Cleveland Clinic Foundation, Cleveland, OH **Massachusetts General Hospital, Boston, MA †Department of Clinical Genetics, University and Regional Laboratories, Skane University Hospital, Lund University, Lund, Sweden ‡Department of Pathology, The Royal Orthopedic Hospital, University of Birmingham, Birmingham, UK ∥Royal Alexandra Hospital, Edmonton, AB ††Montreal Children's Hospital, McGill University Health Center, Montreal, QC, Canada #Middlemore Hospital, Manukau, Auckland, New Zealand.
authors.forename: Alero
authors.initials: A
authors.lastname: Inyang
authors.forename: Fredrik
authors.initials: F
authors.lastname: Mertens
authors.forename: Florian
authors.initials: F
authors.lastname: Puls
authors.forename: Vaiyapuri
authors.initials: V
authors.lastname: Sumathi
authors.forename: Carrie
authors.initials: C
authors.lastname: Inwards
authors.forename: Andrew
authors.initials: A
authors.lastname: Folpe
authors.forename: Cheng-Han
authors.initials: CH
authors.lastname: Lee
authors.forename: Yaxia
authors.initials: Y
authors.lastname: Zhang
authors.forename: Pennie
authors.initials: P
authors.lastname: Symmans
authors.forename: Brian
authors.initials: B
authors.lastname: Rubin
authors.forename: Gunnlaugur P
authors.initials: GP
authors.lastname: Nielsen
authors.forename: Van-Hung
authors.initials: VH
authors.lastname: Nguyen
authors.forename: Andrew E
authors.initials: AE
authors.lastname: Rosenberg
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics; D001706:Biopsy; D001859:Bone Neoplasms / Q000737:chemistry / Q000235:genetics / Q000473:pathology / Q000601:surgery; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D006390:Hemangioendothelioma / Q000737:chemistry / Q000235:genetics / Q000473:pathology / Q000601:surgery; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary / Q000737:chemistry / Q000235:genetics / Q000473:pathology / Q000601:surgery; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D014178:Translocation, Genetic; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor