Clear Cell acanthoma

From dermoscopedia
(2 votes)
 Author(s): Ralph P. Braun, Ofer Reiter
Description This page has not yet been summarized.
Author(s) Ofer Reiter · Ralph P. Braun
Responsible author Ralph Braun→ send e-mail
Status unknown
Status update May 14, 2017
Status by Ralph P. Braun

Also known as "Acanthome cellules claires of Degos and Civatte", "Degos acanthoma," and "Pale cell acanthoma", clear cell acanthoma is a benign clinical and histological lesion initially described as neoplastic, which some authors now regard to as a reactive dermatosis. It usually presents as a moist solitary firm, brown-red, well-circumscribed, 5 mm to 2 cm nodule or plaque on the lower extremities of middle-aged to elderly individuals. The lesion has a crusted, scaly peripheral collarette and vascular puncta on the surface. It is characterized by slow growth, and may persist for years [1].

'String of pearls'

Even though clear cell acanthoma has a non-specific clinical appearance, it has a relatively specific and easy to recognize dermoscopic feature called 'string of pearls', referring to dotted vessels that are arranged in a linear of serpiginous pattern [2]. The linear formations tend to coalesce into a reticular pattern, covering whole or part of the lesion [1]. The 'string of pearls' sign was found to be related to angio-eccrine hyperplasia and vascular hyperplasia of the papillary dermis, corresponding to the cappilaries oriented perpendicular within the elongated dermal papillae [3].

Clear cell acanthoma.jpg

Additional dermoscopic features[1]

  • Pale pink background (90% of cases)
  • Shiny white lines (60% of cases)
  • Glomerular vessels (55% of cases)
  • Collarette of translucent scale around the periphery of the lesion (40% of cases)
  • Haemorrhagic areas (35% of cases)
  • Orange crusts (15% of cases)

CP (5).JPG

Differential diagnosis

The clinical differential diagnosis includes: dermatofibroma, inflamed seborrheic keratosis, pyogenic granuloma, actinic keratosis, basal cell and squamous cell carcinoma, verruca vulgaris, psoriatic plaque, eccrine poroma, clear cell hidradenoma and melanoma [4]. In a recent report it was demonstrated that the 'string of pearls' sign can be seen with other epidermal lesions, as two seborrheic keratoses and one lichen planus-like keratosis presented with the classic 'string of pearls' sign. [5]

  1. 1.0 1.1 1.2 Lyons et al.: Dermoscopic features of clear cell acanthoma: five new cases and a review of existing published cases. Australas. J. Dermatol. 2015;56:206-11. PMID: 25495637. DOI.
  2. Tiodorovic-Zivkovic et al.: Dermoscopy of clear cell acanthoma. J. Am. Acad. Dermatol. 2015;72:S47-9. PMID: 25500041. DOI.
  3. Paolino et al.: Clinicopathological and dermoscopic features of angio-eccrine hyperplasia in clear cell acanthoma. J. Am. Acad. Dermatol. 2016;74:1259-1261.e3. PMID: 27185430. DOI.
  4. Tiodorovic-Zivkovic et al.: Dermoscopy of clear cell acanthoma. J. Am. Acad. Dermatol. 2015;72:S47-9. PMID: 25500041. DOI.
  5. Espinosa et al.: "String of pearls pattern": report of three cases of non clear-cell acanthoma. An Bras Dermatol 2017;92:142-144. PMID: 29267474. DOI.
Cookies help us deliver our services. By using our services, you agree to our use of cookies.