Primary dural lymphoma of the chronic lymphocytic lymphoma/small lymphocytic lymphoma-mimicking meningioma: illustrative case.

BACKGROUND

Lymphomas originating from the dura mater of the skull, known as primary dural lymphomas (PDLs), are rare. Among these, cases of chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) are exceptionally uncommon, and no standardized treatment protocols have been established. The authors report a rare case of CLL/SLL manifesting as PDL mimicking a skull base meningioma and review the relevant literature.

OBSERVATIONS: A 71-year-old male presented with an extra-axial tumor extending from the petroclival to middle cranial fossa, which demonstrated progressive enlargement over the course of 1 year. The preoperative diagnosis was meningioma, and the patient subsequently underwent preoperative embolization followed by partial tumor resection. Histological examination revealed CLL/SLL. Postoperatively, the residual lesion was treated with radiation therapy, and no recurrence has been observed for > 3 years.

LESSONS: CLL/SLL arising as PDL is difficult to distinguish from meningioma based on clinical and radiological findings. However, it generally shows favorable outcomes when treated with a combination of surgery and low-dose radiation therapy. https://thejns.org/doi/10.3171/CASE25831.