The Dermatoscopic Pattern of Clear-Cell Acanthoma Resembles Psoriasis vulgaris

Abstract

Background: Dermatoscopy (dermoscopy, epiluminescence microscopy) is used for the early detection of malignant tumors and avoidance of unnecessary excisions of benign skin tumors. Objective: Description of the dermatoscopic pattern of clear-cell acanthoma. Methods: Video dermatoscopy at 20-fold magnification of a clear-cell acanthoma and psoriasis vulgaris. Results: Homogeneous, symmetrically or bunch-like arranged, pinpoint-like capillaries were seen in the clear-cell acanthoma and in psoriasis vulgaris. Conclusion: The dermatoscopic psoriasis-like pattern of clear-cell acanthoma is a diagnostic clue which may help the clinician to identify this benign epidermal tumor and to differentiate it from other benign and malignant tumors of the skin.

Dermoscopy in General Dermatology

“…From 1955 to January 2005, we found 61 dermoscopy articles reporting a variety of different indications in the context of NPSD [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61]. Preferentially we did not include dermoscopy articles in which the differential diagnosis to pigmented skin tumors was discussed.…”

“…A practical example explaining the application of the dermoscopic algorithm to differentiate NPSD is the following: amelanotic melanoma [3,4,5,6,7] and psoriasis [7,8,9,10,11,12,13] might reveal both dotted vessels by dermoscopy. However, the clinical appearance of a single lesion in the former and the typical location of multiple lesions in the latter, allow distinguishing this highly malignant skin tumor from the harmless plaques of psoriasis (step 1).…”

“…However, the clinical appearance of a single lesion in the former and the typical location of multiple lesions in the latter, allow distinguishing this highly malignant skin tumor from the harmless plaques of psoriasis (step 1). By contrast, amelanotic melanoma [3,4,5,6,7] and clear cell acanthoma [3,10,11,12, 46] can sometimes be indistinguishable by their clinical appearance (fig. 2), whereas dermoscopically, these tumors exhibit specific types and arrangement of vessels, allowing a diagnosis with increased confidence (fig.…”

“…Dermoscopy can also be used for diagnosing pediculosis capitis and pubis, since the dermoscopic examination of affected hairs provides a sufficient magnification for identifying pediculus hominis and pthyrius pubis. Dermoscopic examination of lesions of psoriasis [7,8,9,10,11,12,13], porokeratosis [20], pityriasis rosea [8, 13, 21], lichen planus [8, 9, 22], and Darier disease [23] often reveals specific criteria that may be helpful in selected, clinically equivocal cases (fig. 4, 5).…”

Dermatoscopy and Its Role In Diagnosing Homogenous Dotted Vascular Pattern In a Case Of Dermatofibroma

“…CCA and psoriasis have close dermatoscopic resemblance consisting in homogenous, symmetrically or bunch-like arranged pinpoint capillaries (2,3). The significant features identified for psoriasis are a homogenous vascular pattern, red dots, and light-red background, yielding a diagnostic probability of 99% if all 3 features are present (2,3). The distribution of the dotted vessels in psoriasis is not so reticular, nor even annular as seen in CCA.…”