Vascular tumours

Angiokeratoma

Epithelioid hemangioma (angiolymphoid hyperplasia with eosinophilia)

Lobular capillary hemangioma (pyogenic granuloma

  - Bacillary angiomatosis

  - Verruga Peruana

Masson's Tumour (Intravascular papillary endothelial hyperplasia)

Acro-angiodermatitis / pseudo-Kaposi's sarcoma

Reactive angioendotheliomatosis

Infantile Hemangioma

Glomeruloid hemangioma 

Acquired tufted angioma

Verrucous hemangioma

Cherry angioma/senile angioma

Arteriovenous hemangioma 

Targetoid hemosiderotic hemangioma(Hobnail hemangioma)

Spindle cell  hemangioma / hemangioendothelioma

Kaposiform hemangioendothelioma

Retiform hemangioendothelioma

Papillary intralymphatic angioendothelioma (Dabska's tumour)

Composite hemangioendothelioma

Kaposi's sarcoma

Epithelioid hemangioendothelioma

Angiosarcoma

Glomus tumour

Hemangiopericytoma

2. Fordyce type: The "Fordyce-type" occurs on the scrotal skin of young and adults as a secondary effect to an increased blood pressure in scrotal veins. An equivalent form affecting adult females and occurring analogously on the skin of the vulva has been recorded.

3. Solitary and multiple types:  The "solitary and multiple papular types" of young individuals affect the lower extremities and is considered a consequence of a congenital deficiency of elastic tissue in regional veins.

4. Angiokeratoma circumscriptum:  This is a nevoid hamartomatous lesion arising early in life during infancy or childhood, sometimes in association with other congenital malformation of other sites.

5. Angiokeratoma corporis diffusum: It is a clinical variant of angiokeratoma that is typically associated with an enzyme deficiency in the metabolism of glycoprotein, most notably Fabry disease, resulting in many other systemic manifestations.

Microscopic features: Image1  ; Image2
- Dilatation of papillary dermal vessels forming cavernous spaces.
- Irregular acanthosis and elongation of rete ridges.
- Elongated rete ridges may surround the vessels.
- Thrombosis of some of the vessels
- Collarette at the margin may be  present.
- In Anderson Fabry  disease, frozen section of the lesion reveals PAS positive and Sudan black positive granules in the endothelial cells, pericytes, arrectores pilorum and sweat glands.

Differential diagnosis:
Verrucous hemangioma- Dilated vessels are present in the deeper levels 

Solitary angiokeratoma of the tongue.J Oral Pathol Med. 2006 Apr;35(4) : 252-3.

Angiokeratoma corporis diffusum (Fabry disease).Dermatol Online J. 2005 Dec 30;11(4):8.

Fabry disease: angiokeratoma, biomarker, and the effect of enzyme replacement therapy on kidney function. Arch Dermatol. 2005 Jul;141(7):904-5; author reply 905-6.

Fucosidosis with angiokeratoma. Immunohistochemical & electron microscopic study of a new case and literature review.J Cutan Pathol. 2005 Aug;32(7):506-11.

Vascular tumors of the skin: a selective review.Semin Diagn Pathol. 2004 Aug;21(3):166-218

Multiple Fordyce-type angiokeratomas of the scrotum. An iatrogenic case.Pathologica. 1998 Feb;90(1):46-50.