Giant verrucous porokeratosis with psoriasiform alteration: A rare entity with atypical clinico-histopathologic features

The sample taken from the edge incidentally demonstrated cornoid lamella as vertical column of poorly stained parakeratotic cells with pyknotic nuclei, running through the normally stained surrounding cells along with absence of granular layer in its floor and hypergranulosis of wall. All these findings were in favor of porokeratosis [Figure 3]a and [Figure 3]b. Other sample taken from the center of the lesion revealed characteristic psoriasiform changes such as orthohyperkeratosis, foci of parakeratosis, attenuated granular layer, and moderate papillomatosis. In dermis, dilated tortuous capillaries at the tip of clubbed dermal papilla and moderately dense superficial perivascular lymphocytic infiltrate were seen supporting the psoriasiform changes [Figure 3]c and [Figure 3]d.{Figure 3} The presence of typical cornoid lamella at the margin of verrucous plaque and other histopathologic findings led us to diagnose it as "verrucous porokeratosis" with psoriasiform changes. [3] Due to its verrucous morphology, it was also known as hyperkeratotic or "verrucous porokeratosis." Since its first description, < 40 cases have been reported worldwide to the best of our knowledge. Recently, in a study, a similar pattern of upregulation of certain proteins such as keratins (keratins 16, 6A, 6B, and 17), specific calcium-binding proteins (psoriasin 1, calgranulin A, calgranulin B, and...