Rosai-Dorfman disease with aortic involvement in a 58-year-old man: a case report

We report the case of a 58-year-old man who had Rosai-Dorfman disease (RDD) with aortitis. He developed a mass in the chest wall, for which a partial excision via thoracoscopy was performed. In addition, Takayasu arteritis (TAK) was suspected based on the increased uptake in the aortic wall on fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT). The case was then referred to our institute for treating TAK. However, we speculated whether TAK could be complicated by a mass in the chest wall. We re-examined the chest wall histopathologically and confirmed the diagnosis of RDD. Although treatment with prednisolone, intravenous cyclophosphamide, and other immunosuppressive drugs was initiated, the diameter of the aorta increased, and his arthritis worsened. Therefore, tocilizumab (TCZ) was administered, which suppressed the dilation of the aortic aneurysm. He died due to multiple cerebral infarctions, and an autopsy was performed. Aortitis due to RDD was proved histopathologically. Although RDD is rare, it should be considered as a differential diagnosis of aortitis.