34219 Hypersensitivity Reaction to Tattoo Pigment Secondary to Checkpoint Inhibition

Immune checkpoint inhibitors are known to have a variety of dermatologic side effects, including granulomatous or sarcoidal inflammatory eruptions. Rarely, patients with permanent tattoos have had granulomatous reactions to immunotherapy. We present, herein, a case of a hypersensitivity reaction to purple tattoo in the setting of pembrolizumab. To the best of our knowledge, this is the first case of a non-granulomatous tattoo reaction secondary to a checkpoint inhibitor. The patient is a 43-year-old Caucasian woman with history of stage IIIA melanoma of the right mid back status post wide local excision and positive sentinel node biopsy, on single agent pembrolizumab.