Amelanotic/Hypomelanotic melanoma--is dermatoscopy useful for diagnosis?

Abstract

Background: Amelanotic/hypomelanotic melanoma often leads to delayed clinical diagnosis because its clinical appearance can mimic other hypopigmented skin conditions. Dermatoscopy (dermoscopy, epiluminescence microscopy) is thought to be a helpful diagnostic tool in pigmented skin lesions, but it can be used also in non-pigmented skin tumors due to the recognition of vascular structures not visible to the naked eye.

Objective: 7 amelanotic/hypomelanotic melanomas in 6 patients were analyzed in order to define their dermatoscopic findings using standard pattern analysis.

Methods: Clinical and dermoscopic images of each lesion were obtained using Dermaphot (Heine Optotechnik, Herrsching, Germany), with 10-fold magnification of the lesion and the color slides were converted to digital format using a Kodak Photo CD system.

Results: All 7 amelanotic/hypomelanotic melanomas revealed peculiar dermatoscopic findings, namely, atypical vessels, dotted vessels, and a central pink to white veil. In addition, in 2 patients a slight brownish homogenous pigmentation at the periphery of the lesion was observed. In one case the correct diagnosis was done by an experienced dermatologist using dermatoscopy, whereas in the remaining 6 cases the clinical diagnoses included squamous cell carcinoma, Bowen disease, pyogenic granuloma and basal cell carcinoma. In 2 of 6 patients amelanotic/hypomelanotic melanoma was associated with a previous history of melanoma.

Conclusion: Amelanotic/hypomelanotic melanoma exhibits as a common dermatoscopic denominator atypical vessels, varying in size and shape, usually associated with a central pink to white veil.