title: Ultrastructure and histogenesis of the acral calcified angioleiomyoma.
abstract: We studied the ultrastructure, immunohistochemistry, and histogenesis of the acral calcified angioleiomyoma, observing three concentric zones: (a) pseudocapsular, thin, with spindle-shaped stromal cells (SCs), presenting scarce organelles and expressing CD34, (b) muscular, forming a ring, with smooth muscle cells of heterogenous phenotype (mainly in quantity and thickness of filaments, and in expression of h-caldesmon, αSMA, and desmin), and (c) central, extensive, calcified (spicular and/or star-shaped calcium deposits around collagen fibers), with pericytic involutive vasculature. The intratumoral vessels were thick (several layers of perivascular cells, with a continuum of phenotypes, resembling myopericytoma vessels) and thin (slit-like channels), without adventitial SCs or elastic material. The extratumoral vessels showed adventitial SCs (which contribute to form the tumor pseudocapsule), hyperplasia of the media and intima layers, and/or occlusion of the lumen by a wide, homogenous fibrotic central zone. Histogenetically, the collagenous matrix may act as a mineralization substrate and the calcifying modified pericytes as inductors; intratumoral vessels may originate from the peritumoral vessels or from the vessel where the tumor develops; and extratumoral vessel modifications, mimicking tumor features, concur with a minor repetitive trauma pathogenesis.
authors.affiliation: a Department of Anatomy, Pathology, Histology and Radiology, Faculty of Medicine , University of La Laguna , Tenerife , Spain.
authors.forename: Lucio
authors.initials: L
authors.lastname: Díaz-Flores
authors.affiliation: a Department of Anatomy, Pathology, Histology and Radiology, Faculty of Medicine , University of La Laguna , Tenerife , Spain.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Gutiérrez
authors.affiliation: a Department of Anatomy, Pathology, Histology and Radiology, Faculty of Medicine , University of La Laguna , Tenerife , Spain.
authors.forename: Hugo
authors.initials: H
authors.lastname: Alvarez-Argüelles
authors.affiliation: a Department of Anatomy, Pathology, Histology and Radiology, Faculty of Medicine , University of La Laguna , Tenerife , Spain.
authors.forename: Miriam
authors.initials: M
authors.lastname: González-Gómez
authors.affiliation: b Department of Pathology , Hospiten® Hospitals , Tenerife , Spain.
authors.forename: Maria Del Pino
authors.initials: Mdel P
authors.lastname: García
authors.affiliation: a Department of Anatomy, Pathology, Histology and Radiology, Faculty of Medicine , University of La Laguna , Tenerife , Spain.
authors.forename: Lucio
authors.initials: L
authors.lastname: Díaz-Flores
mesh_terms: D018229:Angiomyoma / Q000175:diagnosis / Q000473:pathology* / Q000648:ultrastructure*; D014408:Biomarkers, Tumor / Q000378:metabolism; D005260:Female; D006393:Hemangiopericytoma / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008875:Middle Aged; D032389:Myocytes, Smooth Muscle / Q000378:metabolism; D020286:Pericytes / Q000648:ultrastructure*; D012983:Soft Tissue Neoplasms / Q000175:diagnosis / Q000473:pathology*; D017154:Stromal Cells / Q000648:ultrastructure
chemical_list: D014408:Biomarkers, Tumor
keywords: Angioleiomyoma; CD34+ stromal cells; calcification; pericytes; smooth muscle cells