Sintilimab-induced severe erosive hemorrhagic gastritis and pyloric obstruction: a case report and literature review

Immune checkpoint inhibitors could restore immune surveillance to attack tumor through targeting CTLA-4, PD-1 or PD-L1, and have achieved huge success. However, immune-related adverse events (irAEs) have been attracting attention as their application is expanding. Gastritis is relatively rare as a subtype of irAEs, particularly severe gastritis. Guidelines on its clinical management still remain undefined due to limited data. Sintilimab is a PD-1 inhibitor approved in China. Here we offer a case of sintilimab-induced severe erosive hemorrhagic gastritis and pyloric obstruction. Conventional proton pump inhibitors and mucosal protective agents did not take effect, so glucocorticoid was chosen. This severe gastritis was successfully cured finally. Our report describing its clinical performances, endoscopic characteristics and treatments, could assist clinicians to better know this rare irAE. Immune checkpoint inhibitors are a type of drug which fight cancer through enhancing the body's immunity. They have significant anti-tumor effects. The side effects of these medications, called immune-related adverse events (irAEs), are becoming more obvious as more and more patients undergo immunotherapy. Sintilimab is an immune checkpoint inhibitor approved in China. This case report discusses an irAE in a patient treated with sintilimab. The patient suffered from gastritis, with severely erosive bloody inflammation and a narrow outflow tract of the stomach. Inhibiting stomach acid and protecting mucosa are classical methods to treat gastritis, but neither worked in this case. However, the patient was successfully treated with glucocorticoids, a type of steroid used to treat inflammation. Gastritis is an uncommon irAE for patients treated with immune checkpoint inhibitors and we are short of credible instructions to timely recognize and manage it. This case report might be valuable for other clinicians looking to treat patients with similar symptoms. A rare case of Sintilimab-induced irAE presented severe diffuse gastritis with pyloric obstruction and responded well to immunosuppression with glucocorticoid.