July 2025—For all the words that have been devoted to the topic of how to meditate, the path to enlightenment can be disarmingly simple: start by noticing. Likewise, there is a fairly simple set of instructions for untangling one of the vexing problems associated with immune checkpoint inhibitors. Though the drugs can create impressive antitumor response, they can also lead to immune-related adverse events (known as irAEs), including colitis and gastritis, which manifest as histologic changes that can be seen in both the upper and lower gastrointestinal tract. Left unaddressed, severe reactions can disrupt treatment. It’s complicated. And it’s not. The first step, says Raul S. Gonzalez, MD, professor of pathology and laboratory medicine and director of the gastrointestinal pathology service, Emory University School of Medicine, is cultivating a certain mindfulness. “We need to have knowledge that checkpoint inhibitors can cause immune-related adverse events such as gastritis and colitis, to be aware that these things happen,” says Dr. Gonzalez.