What Is Your Diagnosis? Elephantiasis Nostras Verrucosa of the Back

A 51-year-old obese man presented to our clinic with a slowly progressive, papillomatous plaque covering a large portion of his back. He initially reported the eruption along the upper back 9 years prior to presentation but had noted a recent insidious progression to involve the majority of the back. The rash was slightly tender; he denied other symptoms including fever, chills, or drainage. Physical examination was notable for a large hyperkeratotic plaque with central pink, friable, papillomatous papules and nodules covering the majority of the back (left). Along the upper shoulder and neck (right) there was a well-defined, erythematous, indurated plaque with a sharp delineation from the surrounding uninvolved skin. A wedge biopsy from the central papillomatous portion of the back and a punch biopsy from the erythematous indurated leading edge of the plaque both revealed lymphangiectasia and epidermal hyperplasia.