Vanishing bile duct syndrome following pembrolizumab infusion: case report and review of the literature

Plain language summary Immunotherapy has demonstrated high efficacy in lung cancer and is commonly used in clinical practice. Despite the good tolerability, severe immune-related adverse events may occur, requiring hospitalization and possibly leading to death. We present a case of vanishing bile duct syndrome (a rare and potentially lethal condition characterized by progressive destruction of small bile ducts) which arose a few days after the first pembrolizumab infusion. Laboratory tests and radiological imaging were performed to orient diagnosis and monitor disease; a histological sample was required for vanishing bile duct syndrome diagnosis. High-dose steroid therapy and immunosuppressors were administered, with scarce efficacy. Prompt recognition and management of similar conditions is crucial to avoid fatal events. Further studies are needed to investigate new drugs for steroid-refractory conditions.