Bullous pemphigoid in elderly woman affected by non-small cell lung cancer treated with pembrolizumab: A case report and review of literature

Introduction Immunotherapy has changed the management of patients with various types of malignancies (melanoma, renal, lung, and bladder cancers) but immune checkpoint inhibitors may be associated with several adverse events. Up to 20% of patients treated with immune checkpoint inhibitors may develop dermatological immune-related adverse events, mostly rashes and pruritus but rarely even bullous pemphigoid. Case report We report a case of an elderly patient with advanced non-small cell lung cancer in therapy with pembrolizumab, 200 mg/body every three weeks. After 26 cycles of therapy, the patient developed widespread itching and then after 28 cycles she developed strained blisters filled with serous fluids on predominantly erythematous skin with suspicious of bullous pemphigoid. Management and outcome:Skin biopsy confirms bullous pemphigoid, so we decided to permanently discontinue therapy with pembrolizumab and the patient is currently on therapy with doxycycline, nicotinamide, and clobetasol propionate with good regression of symptoms and cutaneous lesions. Discussion In the literature, the first case of bullous pemphigoid induced by pembrolizumab has been described in 2015. On Pubmed, from 2015 to date, we have found 19 cases of bullous pemphigoid during pembrolizumab therapy but only three of them are related to non-small cell lung cancer, adding our patient we reach a total of 20 cases. It could be interesting to investigate if there is a specific relationship between the appearance of itching and the development of bullous pemphigoid.