RATIONALE: Immune-checkpoint inhibitors have emerged as a frontline treatment for a growing list of malignancies. Immunotherapy-induced bullous pemphigoid (BP) is a rare dermatological immune-related adverse event of immune-checkpoint inhibitor therapy immune-checkpoint inhibitor therapy. We report a case of immunotherapy-associated BP, with lesions presenting in a photodistribution. This case report aims to emphasize the early recognition of rare clinical manifestations induced by immunotherapy to improve patient prognosis. PATIENT CONCERNS: The patient was a 77-year-old man with a history of right upper lung squamous cell carcinoma on sintilimab (anti-programmed cell death protein-1 [PD-1]) for over a year. After 12 months of initiation of PD-1 inhibitors, nonspecific cutaneous eruption appeared on his head, face, and extremities, mostly pruritic eczematous dermatitis with papules and plaques. The time to development of bullae after medication initiation was 16 months. DIAGNOSES: Sintilimab-induced BP. INTERVENTION: Oral prednisone was gradually tapered to discontinuation following intravenous methylprednisolone
the skin lesions have basically recovered. OUTCOMES: Follow-up for 19 months showed no recurrence of the skin lesions. LESSONS: This case report emphasizes that the clinical manifestations of BP induced by PD-1/programmed death ligand-1 inhibitors can be diverse. Dermatologists need to increase their awareness of BP caused by PD-1/programmed death ligand-1 inhibitors.