Clinical, dermoscopic, and histopathologic findings of hidroacanthoma simplex: a case report and literature review.

Hidroacanthoma simplex (HS) is a rare benign intraepidermal tumor that originates in the acrosyringial portion of the eccrine duct. Clinically, they are well-defined lesions, flat or verrucous brownish plaque, and can be misdiagnosed with other types of benign or malignant tumors. Dermoscopy reveals small black globules and fine scales.