Seborrheic Keratoses By Denise M Aaron, MD, Dartmouth Geisel School of Medicine Reviewed / Revised Jan 2022 | Modified Sep 2022 View Patient Education Diagnosis Treatment Topic Resources Seborrheic Keratosis Seborrheic Keratoses (Back) Dermatosis Papulosa Nigra Leser-Trélat Sign Seborrheic keratoses are superficial, often pigmented, epithelial lesions that are usually warty but may occur as smooth papules.