Multiple Cutaneous Adverse Reactions Secondary to Nivolumab Therapy in an Elderly Male.

Nivolumab is a human IgG4, PD-1 inhibitor that is approved for the treatment of advanced melanoma. We hereby report a patient of metastatic melanoma who developed multiple cutaneous side effects, including Sweet's syndrome, lichenoid eruption, and vitiligo-like depigmentation after initiation of the nivolumab therapy. He first started developing vitiligo-like depigmentation over the lips, which appeared after five months. Later, he developed a mildly itchy lichenoid eruption over the thighs. The most recent and disabling one was the appearance of erythematous edematous painful plaques studded with pustules and vesicles with fever. The latter was diagnosed as Sweet's syndrome. Nivolumab was stopped, and the patient was started on oral dapsone 100 mg per day with topical mometasone 0.1% cream once a day application for these lesions. The patient had complete resolution of edematous plaques after four weeks of follow-up. Also, the subsequent dose of nivolumab was decreased by 20%, and this was not followed by the recurrence of Sweet's syndrome; however, vitiligo-like depigmentation persisted.