[A Case of Primary Dural Lymphoma of Jugular Tubercle Mimicking Lower Clival Meningioma].

Primary dural lymphoma (PDL) is a rare type of primary central nervous system lymphoma (PCNSL); however, its clinical etiology and appearance on magnetic resonance images (MRI) are similar to those of meningioma. We report a case of PDL mimicking a meningioma in the jugular tubercle, with hemiparesis and double vision, and review the published PDL case reports. A 41-year-old woman experienced numbness on her right side, and reported right hemiparesis and double vision 2 days thereafter. Her cranial computed tomography (CT) scan showed a mass lesion in the posterior fossa, and contrasted MRI revealed homogenous tumor with a dural tail sign in the left jugular tubercle. The patient was diagnosed as having jugular tubercle meningioma. However, her symptoms disappeared promptly with the injection of dexamethasone, and follow-up MRI showed that the tumor had diminished. After 9 months, her double vision recurred and MRI results indicated tumor regrowth. She underwent sub-total resection of the tumor via the left trans-condylar fossa approach. A histological diagnosis was PDL. She was treated with 3 courses of high-dose methotrexate, and subsequent MRI results showed a partial reduction of the residual tumor. PDL is histologically associated with marginal zone lymphoma (MZL), and is sensitive to radiation and chemotherapy. This patient responded well to high-dose methotrexate alone. PDL is one of the important differential diagnoses of meningioma.