Histologic Changes in Seborrheic Keratoses after Rubbing

The study examined histologic changes in seborrheic keratoses after rubbing in 5 patients, revealing both acute and chronic changes. Early changes included hemorrhage, hyalinization of dermal papillae, and necrosis of epithelial tips. After 48 hours, changes such as loss of epithelial mass, keratin cyst expansion, epithelial thinning, and proliferation of epithelial strands were observed. There was also an increase in epithelial cell size and evidence of hair follicle relationships, including trichostasis spinulosa and hair germ proliferation in one case. Dermal lymphocytic infiltration varied and rarely affected the epithelium. The findings suggested a patterned response to trauma and a link between seborrheic keratosis and hair follicles.