Bullous disorders associated with anti–PD-1 and anti–PD-L1 therapy: A retrospective analysis evaluating the clinical and histopathologic features, frequency, and impact on cancer therapy

Bullous disorders associated with anti–programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) therapy are increasingly reported and may pose distinct therapeutic challenges. Their frequency and impact on cancer therapy are not well established. To evaluate the clinical and histopathologic findings, frequency, and impact on cancer therapy of bullous eruptions due to anti–PD-1/PD-L1 therapy. We retrospectively reviewed the medical records of patients evaluated by the oncodermatology clinic and consultative service of Yale New Haven Hospital from 2016 to 2018. We identified 9 of 853 patients who developed bullous eruptions (∼1%) that were treated with anti–PD-1/PD-L1 therapy at our institution during the study period: 7 presented with bullous pemphigoid, 1 presented with bullous lichenoid dermatitis, and 1 presented with linear IgA bullous dermatosis in the context of vancomycin therapy. In all, 8 patients required systemic steroids, 5 required maintenance therapy, and 8 required interruption of immunotherapy. All 9 patients had an initial positive tumor response or stable disease, but 4 went on to develop disease progression. This was a retrospective study from a single tertiary care center. Bullous disorders developed in approximately 1% of patients treated with anti–PD-1/PD-L1 therapy at our institution and frequently resulted in interruption of immune therapy and management with systemic corticosteroids and occasionally steroid-sparing agents.