Dermoscopy of Nodular Hidradenoma, a Great Masquerader: A Morphological Study of 28 Cases

Nodular hidradenoma is an uncommon, benign, adnexal neoplasm of apocrine origin which is a clinical simulator of other tumours.

The aim of this study was to evaluate the morphological findings of a large series of nodular hidradenomas under dermoscopic observation.

Dermoscopic examination of 28 cases of nodular hidradenomas was performed to evaluate specific dermoscopic criteria and patterns.

The most frequently occurring dermoscopic features were: (1) in 96.4% of cases, a homogeneous area that covered the lesion partially or totally, the colour of which was pinkish in 46.4% of cases, bluish in 28.6%, red-blue in 14.3%, and brownish in 10.7%; (2) white structures were found in 89.3% of cases; (3) in 82.1% of cases, vascular structures were also observed, especially arborising telangiectasias (39.3%) and polymorphous atypical vessels (28.6%).

Nodular hidradenomas represent a dermoscopic pitfall, being difficult to differentiate clinically and dermoscopically from basal cell carcinomas and melanomas.