Fig. 1.

a Cutaneous neoplasms following fresolimumab treatment. Patient 007 was a 65-year-old woman with MM who received fresolimumab at 1 mg/kg ×4 doses followed by extended treatment at 3 and 15 mg/kg ×4 who achieved a PR. An asymptomatic, self-limited, papular rash developed after three doses of fresolimumab 1 mg/kg. At 3 mg/kg, a papular rash with a few keratosis pilaris-like papules developed, which on biopsy revealed an enlarged hair follicle with irregular keratinization and lichenoid keratosis. Between courses, rashes improved and tumor continued to regress. At 15 mg/kg, lesions with features of keratoacanthomas developed on her face, chest, and arms. These lesions completely regressed over a period of months following completion of therapy. b Characteristic appearance of a keratoacanthoma. Lesions were characterized by skin-colored, dome-shaped papules or nodules with a crateriform center and keratin plug