Abstract
BACKGROUND: Cytokine release syndrome (CRS) is caused by the release of inflammatory cytokines that appear during or immediately after administration of a therapeutic antibody and can cause a variety of symptoms. COVID-19 vaccination is effective in cancer patients and prevents breakthrough infections. The safety of vaccines during immune checkpoint inhibitor (ICI) therapy has been reported; however, multiple vaccinations have been developed in recent years, and it is unclear whether repeated vaccinations play a role in the development of CRS in patients receiving ICI. CASE DESCRIPTION: A 55-year-old man with stage IV non-small cell lung cancer received ipilimumab and nivolumab maintenance therapy; adverse reactions during the first and second COVID-19 vaccinations (BNT162b2) included injection site pain and slight fever; however, the day after the third COVID-19 vaccination (mRNA-1273), he developed a high fever and lost consciousness. Brain MRI showed parietal meningitis. Cytokine levels (IL-6, sIL-2R, IL-10, IFN-γ) were elevated and Grade 2 liver and renal dysfunction were also observed. As various tests ruled out infection and a PCR test for SARS-CoV-2 was negative, a diagnosis of CRS due to COVID-19 vaccination was made. After steroid therapy, his symptoms improved dramatically. CONCLUSIONS: In this case, there was a close association between the time course after vaccination and clinical symptoms of high fever and lost consciousness. Clinicians should be aware of the possibility of vaccine-induced adverse effects such as CRS.