Abstract

A 73-year-old male, presented to the dermatology clinic for evaluation of a pink rough patch measuring 1.7 x 0.8 x 0.1 cm on his left shin, which was further biopsied to rule out malignancy. On histopathological examination, hyperkeratosis, papillomatosis and pseudohorn cysts were seen with flat base. On first glance, the lesion mimicked the features of seborrheic keratosis. On careful close examination, cornoid lamella consisting of angulated, thin, compact column of parakeratosis overlying area of epidermal dysmaturation was also seen. The granular layer was decreased to absent, and occasional dyskeratotic cells were present beneath this foci of parakeratotic column. This case was diagnostically challenging both clinically and histologically. Many subtypes of seborrheic keratoses exist, knowledge of which can be helpful in these difficult cases. Although the etiology is not well established, genetic predisposition and medications may play a role. Herein we report this distinct variant of porokeratosis, which is best identified with clinicopathologic correlation.

Financial Disclosure:
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