History: A 42-year-old man presented with a two year history of an enlarging subcutaneous mass in the right triceps. The excised mass was 3 x 1.5 x 1.2 cm.
Microscopically, the tumor was composed mostly of blood vessels with dilated spaces (Fig. 1, 2). Cuffs of uniform rounded cells were present with punched-out nuclei and eosinophilic cytoplasm. Many of the cells were angiocentric (Fig. 3, 4). Oncocytic changes in glomus cells with abundant granular, eosinophilic cytoplasm were also seen (Fig. 5).
Diagnosis: “Glomuvenous Malformation (Glomangioma)â€
Cynthia X. Zhao, MD, MPH, Hannah Wong, MD, and Donald R. Chase, MD
Department of Pathology and Human Anatomy, Loma Linda University and
Medical Center, Loma Linda, California
California Tumor Tissue Registry, Loma Linda, California
Discussion: Glomuvenous malformation (GVM), formerly known as glomangioma, is a rare, benign vascular neoplasm first described by Masson in 1924. It is an autosomal dominant condition associated to chromosome 1p21-22. It is considered a variant of classic glomus tumor and accounts for about 20% of glomus tumors. It often arises during childhood, but may occur at any age. No sex predilection is reported.
Clinically, GVM presents as red-blue nodules or plaque-like with a distinct raised hyperkeratonic cobblestone appearance. It may be single or multiple. The process occurs most commonly on the extremities involving skin and subcutaneous tissue and can present as painful or painless nodules.
Histologically, GVMs are characterized by the presence of several layers of smooth-muscle-like glomus cells surrounding distended vascular lumens. Glomus cells are modified smooth muscle cells and involved in heat regulation. They are monomorphic round cells with pale eosinophilic cytoplasm and round to oval nuclei. Immunohistochemically, glomus cells stain positively for vimentin and alpha smooth muscle actin, but negatively for desmin, von Willebrand factor and S-100.
The treatment of choice for isolated cutaneous glomuvenous malformation is surgical excision. Other treatment options include sclerotherapy and laser therapy with ablative or pulsed dye.
Differential diagnoses include:
Classic glomus tumors present in the subungual region, but may also occur at other areas. Histologically, blood vessels are lined by normal endothelial cells and surrounded by a solid proliferation of glomus cells, which are round or oval with round nuclei and acidophilic cytoplasm. The lack of vessel space enlargement differentiates it from glomuvenous malformation.
Aneurysmal fibrous histiocytoma most often occurs on the extremities, and can grow rapidly by spontaneous intralesional hemorrhage. Histological features are large blood-filled spaces surrounded by discohesive fragments of tumor, but devoid of an endothelial lining. Prominent hemosiderin deposition, numerous siderophages and giant cells, and a moderate mitotic rate are noted.
Epithelioid hemangioma is a lesion of vascular origin that was first described in 1969. It is most frequently found in the skin and subcutaneous cellular tissue of the head, particularly around the ears. It microscopy shows an abundant vascular proliferation centered around a larger parent vessel. The classic feature of this lesion is the epithelioid endothelial cells. The endothelial cells have rounded or lobular nuclei and abundant acidophilic cytoplasm, containing occasional vacuoles that represent the formation of a primitive vascular lumen. Abundant infiltration of inflammatory cells consisting mainly of eosinophils and more rarely lymphocytes is frequently noted. Immunohistochemically, CD31, CD34 and the antigen associated with Factor VIII typically demonstrate positive immunostaining in tumors with endothelial differentiation.
Suggested Reading:
1．Weiss SW, Goldblum JR. Enzinger & Weiss’ Soft Tissue Tumors. 5th Ed. Mosby, Inc.
2．Chen AY, Eide M, Shwayder T. Glomuvenous malformation in a boy with transposition
of the great vessels: a case report and review of literature. Pediatr Dermatol. 2009 Jan-Feb;26(1):70-4.
3. Henning JS, Kovich OI, Schaffer JV. Glomuvenous malformations. Dermatol Online J. 2007 Jan 27;13(1):17.
4. Fletcher CD, Unni KK, Mertens F. Pathology and Genetics of Tumours of Soft Tissue and Bone. IARCPress. Lyon, 2002.
5. Boon LM, Mulliken JB, Enjolras O, Vikkula M. Glomuvenous malformation (glomangioma) and venous malformation: distinct clinicopathologic and genetic entities. Arch Dermatol. 2004;140(8):971-6.
6. Mallory SB, Enjolras O, Boon LM, et al. Congenital plaque-type glomuvenous malformations presenting in childhood. Arch Dermatol. 2006;142(7):892-6.
7. Glick SA, Markstein EA, Herreid P. Congenital glomangioma: case report and review of the world literature. Pediatr Dermatol. 1995;12(3):242-4.
