DrMihm.com Case File

 Search Dr.Mihm.com

Hobnail Hemangioma - Submitted on: Wednesday February, 26, 2003
Contributed by:Arash Radfar, MD, N/A
Targetoid Hemosiderotic Hemangioma was identified as a separate entity by Santa Cruz et al. at the beginning of AIDS-associated epidemics of Kaposi’s sarcoma as a benign lesion that has to be differentiated clinically and histologically with Kaposi’s sarcoma

Hobnail or Targetoid Hemosiderotic Hemangioma is a benign vascular proliferation clinically often presenting as a targetoid lesion and histologically formed by vascular proliferation lined by plump endothelial cells with large nuclei and small amounts of cytoplasm which protrude in the vascular lumen.

Clinical Features:
Hobnail hemangiomas are more common in males (M:F, 1.36:1). The mean age of occurrence is 32 years with a wide range of distribution. Extremities and back are the most common sites of involvement. There is no report of local recurrence or metastasis following a complete excision of the lesion. The main clinical differential diagnosis is hemangioma, Kaposi’s sarcoma and melanocytic lesions

(Click on an image for a larger view)
Figure 1; Medium power of the lesion shows that the vascular spaces are lined by protruding endothelial cells (“hobnail”).
Figure 2; Medium power of the periphery of the lesion shows a more invasive and penetrating look and peripheral hemosiderine deposition.
Histologically, Hobnail Hemangiomas are vascular proliferations with biphasic growth pattern. Superficially, the lesions are formed by dilated vascular spaces which tend to assume a more invasive and penetrating look toward the periphery and the deeper aspects of the lesion. The vascular spaces are lined by plump protruding endothelial cells (“hobnail”). Hemosiderin deposition is present at the periphery. Dermal fibrosis and lymphocytic infiltrate can also be seen in some lesions. The peripheral hemosiderin deposition is responsible for the targetoid clinical appearance. In mature lesions fibrosis is more prominent with slit-like vascular spaces giving sometimes infiltrative appearance. In early lesions the vascular spaces are more dilated and more superficial. Immunohistochemically, the neoplastic endothelial cells are strongly positive for CD31, and rarely (3/28 cases studied) stain with CD34. In addition, in only 25% of the studied cases, the endothelium-lined spaces are surrounded by actin positive pericytes which distinguish them from endothelial cells in benign hemangiomas which are surrounded by actin positive pericytes in 100% of the cases. Fifty percent of studied cases express VEGFR-3 which suggest a lymphatic line of differentiation. The main histological differential diagnosis is Kaposi Sarcoma.

Simple excisional biopsy is recommended

  • Mentzel T, Partanen T and H. Kutzner. Hobnail Hemangioma (“targetoid hemosiderotic hemangioma”): clinicopathological and immunohistochemical analysis of 62 cases. J. of Cutaneous Pathology, 1999; 26(6): 279-286
  • Santa Cruz DJ, and J Aronberg. Targetoid Hemosiderotic Hemangioma. J AM Acad Dermatol. 1988; 19: 550-8.
  • Santonja C, and A Torrelo. Hobnail Hemangioma. Dermatology 1995;191:154-156.

    Back To Cases


    [Home] [Observations] [Cases] [Glossary] [Who We Are] [Contact Us] [Links] [Search]


    Copyright © 2001-2002 Martin C. Mihm, Jr.
    All  rights reserved worldwide.