Pegfilgrastim-Induced Aortitis in a Patient with Small-Cell Lung Cancer Who Received Immunotherapy Combined with Chemotherapy.

Introduction: Granulocyte colony-stimulating factor (G-CSF), including pegfilgrastim, increases the peripheral blood leukocyte count and is widely used in clinical practice in combination with cytotoxic chemotherapy. The most frequent side effects of G-CSF are pain and fever; aortitis, in contrast, is a rare and serious side effect.

Case Presentation: A 73-year-old man with small-cell lung cancer was treated with a full dose of a combination of carboplatin/etoposide/durvalumab and pegfilgrastim. The patient developed fever and right ear pain 12 days after pegfilgrastim administration and was diagnosed with aortitis by contrast-enhanced computed tomography 5 days later. Because the patient had already been administered the immune checkpoint inhibitor and had a history of hepatitis B, the patient was followed up without corticosteroid administration, and the patient's symptoms resolved spontaneously.

Conclusion: In situations where immunosuppression should be avoided, we believe that follow-up without corticosteroids for G-CSF-induced aortitis is a promising option.