Concentrically expanded reversed halo sign caused by nivolumab-related pneumonia.

Among immune-related adverse events, pneumonitis is relatively uncommon, and nivolumab-related pneumonitis may present with a reversed halo sign.

Comparison of pathological findings and accumulation of fluorin-18 fluorodeoxyglucose on positron emission tomography/computed tomography: A case of relapsing polychondritis.

A 70-year-old woman with a hoarse voice and dry cough was referred to our hospital. Positron emission tomography/computed tomography showed abnormal accumulation of fluorine-18 fluorodeoxyglucose (FDG) at the nasal septum, larynx, trachea, bronchus, and costal cartilages. The maximum standard uptake values of FDG accumulation in the nasal septum and costal cartilage were similar. Biopsies of the nasal septum and costal cartilage were performed. The patient was diagnosed with relapsing polychondritis (RP) based on the clinical features and pathological findings. Histopathological examination revealed progressive initial RP findings. The disease progression was different, even with the same FDG accumulation.