Background: The increasing use of immunotherapy in oncology increases the need for radiologic evaluation of frequent and severe immune-related adverse events.
Objective: Determination of the incidence and manifestation of radiologic and nuclear medicine findings of immune-related adverse events.
Material and methods: Literature review of clinical and imaging findings of immune-related adverse events induced by the immune checkpoint inhibitors ipilimumab, nivolumab and pembrolizumab. Findings are illustrated with pictorial examples and contrasted to other relevant differential diagnoses.
Results: The most frequent imaging manifestations are colitis, hepatitis, pancreatitis, hypophysitis, pneumonitis, arthritis and sarcoid-like lymphadenopathy. Severe to life-threatening complications may result from colitis, pneumonitis and hypophysitis. A clear differentiation from other autoimmune diseases and discrimination of immune-related and infectious pulmonary findings can be very difficult and need close multidisciplinary collaboration.
Conclusion: Knowledge of clinical and imaging findings of adverse events induced by immunotherapy is essential for timely and adequate therapeutic decisions. In addition to staging and follow-up imaging, identification and monitoring of immune-related adverse events adds to the radiologic responsibility in oncologic care.
Keywords: Computed tomography; Imaging results; Immune checkpoint inhibitors; Immune-related adverse events; Magnetic resonance tomography.