Angiokeratoma circumscriptum is a cutaneous lesion of dark red or reddish blue color. It is a benign vascular disorder that doesn't require any special treatment, but is usually resected for cosmetic reasons and because malignancies may be misdiagnosed as angiokeratomas.
AC may be present at birth or develop at a later point in time . Patients more often present with unilateral, solitary lesions than with bilateral disease or multiple AC. Besides cutaneous alterations as described below, the vast majority of AC patients remains asymptomatic. However, they may claim tenderness  .
AC are usually of dark red or reddish blue color, much like hematomas, but are raised above the skin surface. They are prone to bleed, and intradermal hemorrhages may cause the lesion to change color rapidly. AC appear as well-demarcated papules or plaques that frequently have irregular borders and a verrucous surface. In the case of multiple lesions, band-like patterns, and linear arrangements prevail. Most commonly, AC affect the distal portions of either lower limb, the thighs or buttocks. However, these angiokeratomas may develop virtually anywhere. Additionally, AC of the tongue and buccal mucosa have repeatedly been described .
It is of utmost importance to distinguish AC from malignant melanoma and other skin tumors  . Histopathological analyses of biopsy specimens may strongly support the clinical diagnosis. Characteristic findings are :
- Hyperkeratosis (orthokeratosis or parakeratosis)
- Thin-walled, dilated capillaries in the papillary dermis
- Occasionally, vascular alterations comprise the reticular dermis
- Thrombosis of ecstatic vessels
AC have been shown to stain positive for lymphatic markers such as podoplanin and Prox1 .
Additional studies, namely biochemical and molecular biological analyses, may be indicated to rule out Fabry disease .
Contrary to untreated Fabry disease and malignancies of the skin, this disease follows a benign course and treatment is generally not required. [symptoma.com]
We recommend VPPDL and LPPAL for the treatment of extensive AC. [ncbi.nlm.nih.gov]
Angiokeratoma circumscriptum lesions are asymptomatic benign vascular malformations that require no treatment. Nevertheless, surgical treatment is often rendered for cosmesis or because of clinical concern regarding the possibility of melanoma. [emedicine.medscape.com]
The treatment options include removal of the tumor through surgery The prognosis of Verrucous Hemangioma is good with suitable treatment. [dovemed.com]
Prognosis Angiokeratoma circumscriptum lesions are asymptomatic benign vascular malformations that require no treatment. Laser ablation has proven highly effective and may offer the best cosmetic outcome. [emedicine.medscape.com]
Klippel-Trenaunay syndrome: diagnostic criteria and hypothesis on etiology. Ann Plast Surg. 2008;60(2):217–23. Jindal SR, Chalvade P, Jerajani HR. Late onset palmar angiokeratoma circumscriptum: An unusual presentation. [ijord.com]
Exact etiology of KTS is not known. A primary mesodermal abnormality in fetal development leads to persistence of microscopic arteriovenous communications. [ijpd.in]
Etiology: a. A striking predilection for the skin of the head. b. Most patients are in the seventh to eighth decade 2. [web.sapmed.ac.jp]
[…] that was associated with bilateral varicoceles. 4 The onset is usually after the age of 40 years. 5 The prevalence is reported to increase with age, from 0.6% in 16-year-old males to 17% in those older than 70 years. 5 The condition is not familial. 5 Etiology [consultant360.com]
Overall, altered hemodynamics (typically caused by trauma) appear to produce telangiectatic vessels of the papillary dermis with an overlying reactive hyperkeratosis to the epidermis.  Epidemiology Frequency United StatesThe frequency of angiokeratoma [thehealthscience.com]
Topics covered includes: Epidemiology of Contact Dermatitis, Animal Models of Contact Dermatitis, Keratinocytes, Innate Immunity and Allergic Contact Dermatitis, Topical Delivery of Haptens: Methods of Modulation of the Cutaneous Permeability to Increase [freebookcentre.net]
Overall, altered hemodynamics (typically caused by trauma) appear to produce telangiectatic vessels of the papillary dermis with an overlying reactive hyperkeratosis to the epidermis.  Epidemiology Frequency The frequency of angiokeratoma circumscriptum [emedicine.medscape.com]
Parra Cares Actas Dermo-Sifiliográficas. 2014; 15 Epidemiology of Hidradenitis Suppurativa: Prevalence, Pathogenesis, and Factors Associated with the Development of HS Inge E. Deckers,Hessel H. Zee,Errol P. [idoj.in]
Angiokeratoma circumscriptum has also been called angiokeratoma corporis naeviform and may be best classified as a type of capillary malformation. [6, 7] Pathophysiology As Imperial and Helwig discussed in 1967, angiokeratomas are not true angiomas but [thehealthscience.com]
Several causal factors, such as congenital development, pregnancy, trauma,  subcutaneous hematomas, and tissue asphyxia, have all been proposed (see Pathophysiology ). Ozdemir R, Karaaslan O, Tiftikcioglu YO, Kocer U. [emedicine.medscape.com]
The pathophysiology of the lesion is discussed with a review of the pertinent literature. It appears that LC primarily affects the subcutaneous tissue in the form of cystic dilatation of lymphatic channels without systemic lymphatic communication. [link.springer.com]
Rapidly find the answers you need with separate sections on diseases and disorders, differential diagnosis, clinical algorithms, laboratory results, and clinical preventive services, plus an at-a-glance format that uses cross-references, outlines, bullets [books.google.com]
But, many are known to reappear following their removal Please find comprehensive information on Verrucous Hemangioma regarding definition, distribution, risk factors, causes, signs & symptoms, diagnosis, complications, treatment, prevention, prognosis [dovemed.com]
Angiokeratomas are benign cutaneous lesions characterized by ectasia of papillary dermis vessels and secondary epidermal changes like hyperkeratosis . It is important to note that they are not neoplasms . Patients may present with solitary or multiple angiokeratomas that develop in distinct parts of the skin, differ in size and surface appearance. Accordingly, the following subtypes are distinguished  :
- Angiokeratoma circumscriptum (AC), either solitary or arranged in a band-like pattern, most commonly affecting the legs
- Angiokeratoma corporis diffusum, multiple pinpoint lesions seen in patients suffering from Fabry disease, a lysosomal storage disorder 
- Angiokeratoma of Mibelli with acral localization
- Angiokeratoma of Fordyce affecting scrotum, penis or vulva 
- Solitary or multiple angiokeratomas
AC is the least common type of angiokeratoma and may be associated with Klippel-Trenaunay-Weber syndrome, Cobb syndrome, and other vascular malformations. Women are affected significantly more often than men. Contrary to untreated Fabry disease and malignancies of the skin, this disease follows a benign course and treatment is generally not required. The latter does not apply, however, if doubts remain as to the nature of the papule or plaque, or if patients request therapy for cosmetic reasons. Treatment may comprise the surgical excision of the respective lesions, but this approach may not be feasible in case of extensive AC. Laser therapy is increasingly applied in those cases.
- Lorgeou A, Chiaverini C, Le Duff F, Lacour JP, Passeron T. Successful treatment of angiokeratoma circumscriptum naeviforme with long pulse alexandrite laser. J Eur Acad Dermatol Venereol. 2016.
- Happle R. Capillary malformations: a classification using specific names for specific skin disorders. J Eur Acad Dermatol Venereol. 2015; 29(12):2295-2305.
- Imperial R, Helwig EB. Angiokeratoma. A clinicopathological study. Arch Dermatol. 1967; 95(2):166-175.
- Trindade F, Torrelo A, Kutzner H, Requena L, Tellechea O, Colmenero I. An immunohistochemical study of angiokeratomas of children. Am J Dermatopathol. 2014; 36(10):796-799.
- Schiffmann R, Ries M. Fabry Disease open link: A Disorder of Childhood Onset. Pediatr Neurol. 2016.
- Patrizi A, Neri I, Trevisi P, Landi C, Bardazzi F. Congenital angiokeratoma of Fordyce. J Eur Acad Dermatol Venereol. 1998; 10(2):195-196.
- Das A, Mondal AK, Saha A, Chowdhury SN, Gharami RC. Angiokeratoma circumscriptum neviforme: An entity, few and far between. Indian Dermatol Online J. 2014; 5(4):472-474.
- Dumitrache N, Neiderer K, Martin B, Dancho J. Angiokeratoma presenting as a melanoma: a case report. J Am Podiatr Med Assoc. 2013; 103(3):241-242.
- Sadana D, Sharma YK, Dash K, Chaudhari ND, Dharwadkar AA, Dogra BB. Angiokeratoma circumscriptum in a young male. Indian J Dermatol. 2014; 59(1):85-87.
- Aggarwal K, Jain VK, Jangra S, Wadhera R. Angiokeratoma circumscriptum of the tongue. Indian Pediatr. 2012; 49(4):316-318.
- Ozdemir R, Karaaslan O, Tiftikcioglu YO, Kocer U. Angiokeratoma circumscriptum. Dermatol Surg. 2004; 30(10):1364-1366.