Background The dermoscopic morphology of apocrine hidrocystomas remains to be elucidated.
Objective To evaluate the morphological findings of apocrine hidrocystomas under dermoscopic observation.
Methods Dermoscopic examination of 22 cases of apocrine hidrocystomas was performed to evaluate specific dermoscopic criteria and patterns.
Results The most frequently occurring dermoscopic features were found to be: (i) A translucent to opaque, homogeneous area which occupies the whole lesion in all apocrine hidrocystomas (100%). The colour of this homogeneous area was skin-colored in 31.8% of our cases; yellow, in 31.8% and blue, in 22.7% of apocrine hidrocystomas. (ii) Vascular structures were identified in 81.8% of our cases; arborizing vessels, in 68.2% and linear-irregular vessels in 9.1% of our cases; and (iii) Whitish structures were identified in 22.7% of the lesions. The results of our study reveal that the presence of a homogeneous area that occupies the whole lesion and arborizing vessels is the most common dermoscopic pattern in apocrine hidrocystomas (68.2%).
Conclusion Apocrine hidrocystomas, above all in its pigmented variant, may represent a dermoscopic pitfall, being difficult to differentiate clinically and dermoscopically from basal cell carcinomas.