Primary Lymphomas of the Skull Base from a Neurosurgical Perspective. Review of the Literature and Personal Experience

Primary lymphomas of the skull base are exceedingly rare and thus not commonly dealt with in everyday clinical practice. Primary diffuse large B cell lymphoma is the most commonly found (30-40% of primary non-Hodgkin lymphomas of the bone). This article reports a case of primary lymphoma of the skull base and reviews all the relevant literature in the PubMed, National Institutes of Health Library, and Google Scholar databases to outline the clinical, diagnostic, and surgical traits of this yet widely unexplored pathology. The incidence of cases peaks between 60 and 70 years of age; those affected tend to be mostly male. The clinical presentation of this pathology is usually abrupt with headache and acute deficit of cranial nerves that improves dramatically with intravenous corticosteroid therapy. The abducens nerve is most commonly involved. Imaging can be unclear because corticosteroid medications can significantly alter magnetic resonance imaging findings, at least in the early stages of the disease, similarly to what happens for primary brain lymphomas (the ghost tumor). Cavernous sinus, parasellar region, upper clivus, and Meckel cave are usually found to be already affected by the time a diagnosis can be made. The intracavernous internal carotid artery is usually encased by the lesion rather than displaced. Because of the anatomical pattern of primary lymphomas of the skull base and their well-known chemosensitivity, surgery is usually only used for diagnosis. Surgical approaches for primary lymphoma of the skull base include transcranial and transnasal-transsphenoidal endoscopy and microsurgery as well as other minimally invasive techniques. Due to the rarity of this neoplasm, there are no definitive data regarding the overall survival rate among patients.