Endocrine effects of immunotherapy for cancer

Modern cancer immunotherapies have changed the way many cancers are treated. Their use is now first line in many advanced malignancies. These therapies, including immune checkpoint inhibitors (iCPIs), involve directing T cell activity against cancer cells. Adverse effects or immune-related adverse events (irAEs) are common and can affect any system. Endocrine organs are particularly vulnerable to dysfunction because of the underlying mechanism of action. Given their increasing use and rapid advances in the field it is imperative that specialists in both oncology and endocrinology keep up to date on the latest guidelines and protocols for recognizing and treating endocrine irAEs. It is essential to implement strategies that ensure minimal disruption to the anti-cancer therapy during the investigation and diagnosis of irAEs. Here we discuss the various endocrine irAEs described in the literature, focusing on those related to iCPI use. Using up-to-date data, we describe the natural history expected in these conditions. Importantly, as newer iCPI agents are introduced the rates of endocrine irAEs appear consistent.