Giant cell arteritis secondary to combined nivolumab and ipilimumab in metastatic pleural mesothelioma

We report a rare case of isolated giant cell arteritis caused by combined immunotherapy with nivolumab and ipilimumab in metastatic pleural mesothelioma. Whilst combination immunotherapy is thought to provide synergistic anti-tumor effects in metastatic malignancies, it has also been associated with an increased frequency of severe immune-related adverse effects. To our knowledge, giant cell arteritis has been described in only four previous cases in relation to single agent immunotherapy, and our patient is the first reported case of isolated giant cell arteritis from combination immunotherapy. This report adds to the literature a rare case of an important adverse effect that clinicians should be aware of, especially with increasing use of combination immunotherapy.