Skull Base Lymphoma: Radiographic Presentation and Surgical Management

Introduction: The frequency of lymphoma involving the central nervous system has been increasing over the last few decades, even among immunocompetent patients. Radiographically, lymphoma has been known to mimic different disease processes. Therefore, surgeons of the head and neck usually include this disease when formulating a differential diagnosis. We describe multiple cases of intracranial lymphoma that were initially consistent with other types of tumors and their surgical management as done via an endoscopic endonasal approach (EEA).

Case Reports: Case #1: 69-year-old female presented with a several month history of headache and an associated 2 week history of double vision. An MRI of her brain showed a clival tumor with associated mass effect onto the cavernous sinuses bilaterally; the lesion was consistent with a chordoma. Via an EEA, a successful debulking of her cavernous sinus was achieved after her frozen section result showed evidence of lymphoma. Her final pathology was found to be diffuse large B cell lymphoma.

Case #2: 57-year-old male presented with a history of headache and diplopia. A brain MRI was ordered that showed a heterogeneously enhancing clivus that appeared abnormally expanded. There was also extraosseous enhancement into the cavernous sinuses and superior orbital fissures bilaterally, the sella, as well as Meckel's cave on the left. He proceeded with an EEA and his superior orbital fissures were decompressed successfully. Final pathology was consistent with diffuse large B cell lymphoma.

Case #3: 76-year-old male presented with a history of recent epistaxis. An MRI of his orbits was obtained which showed a mostly homogenously enhancing mass involving the left nasal cavity and bilateral ethmoid air cells. There was extension of this mass into the left sphenoid sinus and left orbit with associated enhancement of the skull base involving the cribiform plate and planum sphenoidale. He presented for an EEA to resect the mass. Frozen section was consistent with esthesioneuroblastoma. However, final pathology proved to be large B cell lymphoma.

Case #4: 58-year-old male presented with a one-month history of deteriorating left eye function. He had an MRI of his brain completed which showed a large, heterogeneously enhancing lesion of his sella with invasion into the bilateral cavernous sinuses, greater on the left than the right. The most likely diagnosis given to the lesion based on imaging was a pituitary macroadenoma. He had an EEA done and frozen section corroborated this diagnosis. During the procedure, the left cavernous sinus and the superior orbital fissures were decompressed. Final histologic analysis revealed diffuse B cell lymphoma.

Conclusion: Lymphoma should always be included in the differential when considering tumors that invade and expand normal osseous components and dural compartments of the intracranial space. Because patients with expansile skull base lesions typically have cranial nerve involvement, decompressing foramen or bone passages through which these nerve pass is an important goal during surgery to regain function. In our opinion, often biopsy alone is not sufficient to manage these patients' disease process.