Case Presentation: A 67-year-old woman with a history of metastatic squamous cell carcinoma of the lungs and plaque psoriasis presented with subacute pruritic and painful descaling lesions of the skin after pembrolizumab maintenance therapy (Figure 1.A). The lesions on the skin were erythematous and desquamating, worse in the upper extremities, lower extremities, abdomen, and trunk. [...]