Severe immune-related adverse event colitis successfully treated with single-dose infliximab in an older adult with hepatocellular carcinoma receiving STRIDE therapy.

[BACKGROUND] Severe immune-related adverse events (irAEs) in steroid-refractory patients remain a clinical challenge among older patients with hepatocellular carcinoma (HCC) treated with immune checkpoint inhibitors. Although infliximab is recommended for steroid-refractory irAE colitis, its safety and outcomes in older patients with liver disease remain unclear. Here, we report a case that highlights the safety and effectiveness of single-dose infliximab for steroid-refractory irAE colitis in an older patient with HCC.

[CASE PRESENTATION] An 84-year-old man with alcohol-related HCC received STRIDE therapy (durvalumab plus tremelimumab). On day 35, he developed a severe headache, followed by watery and bloody diarrhea on day 40. Based on the clinical course and endoscopic findings, the patient was diagnosed with grade 4 irAE colitis. His condition was refractory to prednisolone (60 mg/day), and a single dose of infliximab (400 mg) was administered on day 5 of steroid therapy. Rapid clinical improvement and remission were observed, and lenvatinib was resumed on day 220 without irAE recurrence.

[CONCLUSION] Single-dose infliximab may be a safe and effective option for severe irAE colitis in older patients with HCC, allowing continuation of cancer therapy. This case may serve as a practical reference for clinicians managing severe irAEs in high-risk populations.