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Table of Contents
Definition / general | Terminology | Epidemiology | Sites | Etiology | Clinical features | Case reports | Treatment | Dermoscopy | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Differential diagnosisCite this page: Shankar, V. Microvenular hemangioma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/softtissuemicrovenularhemangioma.html. Accessed March 19th, 2019.
Definition / general
- Dermal proliferation of small, irregular branching capillaries and venules with inconspicuous lumina
Terminology
- First described in 1989 as microcapillary angioma (Z Hautkr 1989;64:1071) and in 1991 with current terminology (J Cutan Pathol 1991;18:235)
Epidemiology
- Rare; < 50 cases reported
- Young to middle aged adults
Sites
- Often trunk or limbs
Etiology
- May be form of acquired venous hemangioma
- Microcapillary hemangioma: similar histology, but occurs in young women taking oral contraceptives or during pregnancy
Clinical features
- Presents as slow growing, solitary, asymptomatic, purple red papule or plaque, 0.5 - 2 cm, usually extremities
- May mimic an inflammatory lesion (J Plast Reconstr Aesthet Surg 2009;62:e166)
Case reports
- Boy with coexisting AML (Pediatr Dermatol 2003;20:266)
- 23 year old woman with slowly growing, solitary red plaque on back (Pathol Int 1998;48:237)
- 28 year old man with thigh nodule (Case of the Week #80)
- 40 year old woman (Dermatology 2003;206:161)
- 53 year old woman with numerous bilateral macules, patches, and plaques (Am J Dermatopathol 2013;35:98)
- 55 year old woman with POEMS syndrome and HHV8+ microvenular hemangioma (Arch Pathol Lab Med 2003;127:1034)
Treatment
- Excision is curative
Dermoscopy
- Multiple well demarcated red globules; fine pigment network at periphery (Dermatology 2007;215:69)
Gross images
Images hosted on other servers:
Well defined, oval red lesion
Microscopic (histologic) description
- Dermal proliferation of small, irregular branching capillaries and venules with inconspicuous lumina
- Endothelial cells may be plump, but no atypia
- Stroma is collagenous
- Variable lymphocytes
- No fat invasion, although may grow along collagenous septa of subcutis
- No spindle cells
Microscopic (histologic) images
Images hosted on PathOut server:
Case of the Week #80:
Images hosted on other servers:
Dermal vascular proliferation
HHV8+ tumor
Positive stains
- Endothelial cells: CD34, CD31, Factor VIII related antigen, vWF, Ulex europaeus lectin
- Pericytes: smooth muscle actin
Negative stains
Differential diagnosis
- Acquired (tufted) angioma: multiple vascular lobules similar to pyogenic granuloma but more cellular, resembling cannonballs
- Kaposi's sarcoma - patch stage: irregular vascular spaces are anastomosing but not collapsed, and are accompanied by atypical endothelial cells, eosinophilic hyaline globules, plasma cells and fascicles of spindle cells; may be irregular dissection of collagen bundles by vessels; spindle cells are HHV8+, patients are HIV+ (Am J Clin Pathol 2004;121:335)
- Kaposiform hemangioendothelioma: also has slit-like lumina, but they are due to nodules and sheets of compact spindle cells; affects the skin or retroperitoneum of infants and children, may be associated with severe coagulopathy
- Sclerosing hemangioma
- Statis related change
