gms | German Medical Science

Objective: Primary central nervous system lymphomas (PCNSL) are a rare occurence in general population with incidince of 0,5 per 100.000. 2-4% of all primary tumors of the brain are PCNSLs. Manifestations are often supratenorial-periventricular. Clinical symptoms could be unspecific and depend on localisation of the lesion. We describe an extra-axial localisation in the right Meckel’s cave including consecutive trigeminal neuralgia, which was initially diagnosed as giant cell arteriitis (GCA).

Methods: Primarily, a 63 year old female suffered from neuropathic pain in the lower right facial quadrant. At time of consultation, symptoms persisted for 9 months. 3 months after onset, she was prescribed pregabalin and carbamazepine for an assumed trigeminal neuralgia without success. She developed hypesthesia in the lower-right quadrant of her face, diplopia and temporal pain while chewing. MRI showed an inflammation of the right temporal artery. Biopsy was negative for GCA. The symptoms improved under steroid therapy and pain and diplopia returned after its ending. Further MRI revealed a contrast enhanced lesion in right Meckel’s cave with compression of the right trigeminal nerve.

Results: Exploration, biopsy and mass reduction of the lesion was performed by right subtemporal approach under functional intraoperative neuromonitoring. Hypesthesia, pain and diplopia subsided completely because of steroid therapy. Tissue sample showed large B-cell lymphoma. Staging detected no other lesions extracranial. Finally, the patient recieved immunochemotherapy consisting of rituximab, methotrexate, cytarabine and thiotepa in our departement of oncology.

Conclusion: If there is suspected GCA without positive biopsy, which is about 10% of cases, further investigations including repeated cranial MRI with and without contrast should be performed to rule out a possible trigeminal neuralgia. In rare cases as we reported in our case, lesions in Meckel’s cave are the cause for the symptoms and even more rare are lymphomas in that region. Tissue sampling and exploration is required to plan further treatment regime. Debulking can be performed to reduce symptoms.

Figure 1 [Fig. 1], Figure 2 [Fig. 2]