LAUSR

Abstract Rationale: Rosai–Dorfman disease (RDD) is a rare benign histiocytic proliferative disease. RDD with cranio-spinal involvement in the foramen magnum is extremely rare. To the best of our knowledge, only 4 cases of RDD with craniocervical junction involvement have been reported so far. Herein, we present the fifth case of RDD with craniocervical junction. Patient concerns: A 26-year-old female presented with a sudden headache, accompanied by nausea and vomiting several times during the past half-month. Diagnoses: Magnetic resonance imaging (MRI) showed a well-defined, lobulated, homogenous mass in the left foramen magnum. The lesion was isointense on T1-weighted images (T1WI) and hypointense on T2-weighted images (T2WI), and showed homogeneously obvious enhancement following the intravenous administration of gadolinium. It was dural based and extending inferiorly along the spinal dura up to the cervical spinal canal. The brainstem was compressed and deflected to the right side. Initial diagnosis of meningioma with craniocervical junction involvement in the foramen magnum was made according to MRI findings. Final diagnosis of RDD was confirmed by histopathological and immunohistochemical examinations after subtotally surgical resection. Interventions: The bulk of lesion in the foramen magnum was removed surgically with suboccipital craniectomy because of brainstem compression. Outcomes: The patient recovered well and was discharged 17 days after the surgery. Lessons: RDD should be considered in patients with dural-based, extra-axial, well-circumscribed, hypo- to isointense on T1WI, hypo- to isointense on T2WI, enhancing intracranial or spinal lesions or both.