Abstract

Breakthrough targeted therapies have produced significant improvements in survival for cancer patients, but have a propensity to cause cutaneous immune related adverse events (irAEs). Psoriasiform reactions represent approximately 4% of dermatologic toxicities seen with immune checkpoint inhibitor (ICI) therapy. In most cases, these irAE are mild, occur in older patients, and present as an exacerbation of existing psoriasis after several doses of ICI therapy. We report a case of a 58 year-old female with metastatic esophageal adenocarcinoma who developed a rash 3 days after initiation of nivolumab therapy. She had no prior history of psoriasis or other rash. She initially presented with well-demarcated psoriasiform plaques on the trunk and extremities studded with peripheral pustules. She had concurrent acrodermatitis enteropathica, clinically diagnosed and confirmed with a low serum zinc level, that improved with supplementation. Her plaques progressed to confluent erythroderma with pustules over 2 weeks despite topical steroid use. Biopsy of the back confirmed intraepidermal spongiform pustules of Kogoj and psoriasiform dermatitis with eosinophils. Her irAE was refractory to systemic steroids and acitretin, prompting discontinuation of nivolumab and treatment of her cutaneous irAE with ustekinumab with a slow taper of acitretin and prednisone. Pustular psoriasis is a rare but severe cutaneous irAE to ICI therapy. Although the severity of psoriasiform irAE appears to be a positive predictor of antitumor response, these reactions often require discontinuation of ICI therapy. Treatment of psoriasiform irAE with secukinumab, without compromising ICI antitumor activity, has been reported. Given the diverse morphologic types of cutaneous irAEs that can occur during ICI therapy, the clinical and histopathologic examination of dermatologic toxicities will be critical to identify patients that may benefit from biologic therapy.

Financial Disclosure:
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