Acquired elastotic hemangioma-like changes and eccrine sweat duct squamous metaplasia in lichen simplex chronicus/prurigo nodularis-like lesions of the knee and elbow.

Background The so-called acquired elastotic hemangioma (AEH) represents a peculiar vascular lesion affecting the sun-damaged skin of the extensor surface of the forearms or the lateral aspect of the neck of middle-aged or elderly women. Methods This is a clinicopathological and immunohistochemical study of a series of 6 lesions located on the knee or elbow showing epithelial features of lichen simplex chronicus (LSC)/prurigo nodularis (PN) with a marked subepidermal vascular proliferation closely resembling AEH. Results Microscopically, all cases of cutaneous lesions showed epithelial features of LSC/PN, that is compact hyperkeratosis with focal parakeratosis, irregular acanthosis, prominen…