Sarcoid-like granulomatosis of the lung related to immune-checkpoint inhibitors: Distinct clinical and imaging features of a unique immune-related adverse event

Abstract

With the rapidly expanding role of immune-checkpoint inhibitor therapy in advanced cancer treatment, an increasing number of new immune-related adverse events (irAEs) are being reported.The present report describes sarcoid-like granulomatosis of the lung as a distinct type of irAE with characteristic clinical, imaging, and histologic features. In patients treated with immune-checkpoint inhibitors, sarcoid-like granulomatosis of the lung presented with a focal area of consolidation in the lung, which was often nodular or round, in the absence of new or enlarging lymphadenopathy on imaging. Histologic examination demonstrated nonnecrotizing granulomas and an absence of malignant cells.The patients were free of new or worsening respiratory symptoms, despite the development of lung parenchymal consolidations. Holding the immune-checkpoint inhibitors led to the spontaneous resolution of the findings, without any specific treatment for the abnormality.Awareness of the manifestations of sarcoid-like granulomatosis of the lung as a distinct type of irAE will improve management of patients treated with immune-checkpoint inhibitors.