Primary Meningeal T-Cell Lymphoma at the Clivus Mimicking a Meningioma

BACKGROUND: Most primary lymphomas of the central nervous system (CNS) are of B-cell origin and are found intra-axially, with a few reported cases of skull base tumors involving the upper clivus or sellar region or both. In this case, a tumor resembling a clivus meningioma without osseous involvement was surgically removed and turned out to be a primary T-cell lymphoma. CASE REPORT: A 60-year-old woman presented with slight right-sided abducens nerve palsy. Cranial imaging revealed an extra-axial mass at the caudal clivus resembling a meningioma. The tumor was removed surgically; smear preparations obtained intraoperatively were inconclusive presumably because of preoperative steroid treatment. The final diagnosis was peripheral T-cell lymphoma, not otherwise unspecified. The patient developed a secondary meningiosis supposedly caused by surgery. CONCLUSIONS: Although a very rare entity among primary T-cell lymphomas of the CNS, these tumors also can occur as skull base lesions without involvement of the bone. Preoperative steroid medication may complicate intraoperative histologic assessment and lead to inadequate treatment of these tumors.