Clinical characteristics, diagnosis, treatment, and prognosis of nivolumab induced gastritis.

Gastritis has recently been reported to be associated with nivolumab, and the clinical characteristics of nivolumab induced gastritis remain unclear. To explore the clinical characteristics of nivolumab induced gastritis, and to provide reference for the classification and treatment guidelines of immune checkpoint inhibitors -related gastritis. Case reports, case series, and clinical studies of nivolumab induced gastritis were retrospectively analyzed by searching the database from the establishment of the database until September 30, 2023. Forty-seven were included, with a median age of 57 years (range 16, 93). The median time of symptom onset was 6 months (range 0.5,36) and 6.5 cycles (range 2, 62). Nausea (29 cases, 61.7%), vomiting (29 cases, 61.7%), and epigastric pain (28 cases, 59.6%) were the most common complaints. Esophagogastroduodenoscopy mainly showed erythema (28 cases, 59.6%). Gastric mucosa biopsy showed epithelial inflammatory cell infiltration (22 cases, 46.8%) and apoptosis (15 cases, 31.9%). Most patients' symptoms and gastric mucosa improved or recovered after receiving systemic steroid and proton pump inhibitor therapy regardless of whether nivolumab was discontinued. Two patients died from gastritis related events. Gastritis should be considered as the cause of unexplained epigastric symptoms in the administration of nivolumab. Understanding the clinical features of nivolumab induced gastritis is very important for accurate diagnosis and timely management of these patients.