Pseudo-Pseudotumor Cerebri (video)

Imaging of the spine was recommended. The abnormal CSF suggested a meningeal process, and we had no explanation for what seemed to be bilateral papilledema. The two LPs were technically difficult and painful and we were concerned about a spinal cord/spinal meningeal neoplasm. Spinal imaging was not done and instead, his evaluation focused on looking for evidence of lymphoma (because of the few plasmacytoid/plasmablasts seen on first LP). A repeat LP under fluoroscopy (07/31/2015), which was again difficult and painful, showed CSF-OP 24cm, only 1cc of CSF was obtained and sent to pathology; cytology was negative. His symptoms did not improve. Repeat SPEP was unchanged. CBC showed mildly elevated WBC. He had normal chest/abdomen/pelvis CT (05/26/2015), hematology evaluation (08/12/2015) followed by a bone marrow biopsy (09/03/2015), bone survey, chest X-Ray, whole body PET-CT (09/02/2015). Ophthalmologic examination (09/10/2015) was unchanged with persistent bilateral disc edema and stable VF. He still complained of severe headaches and fluctuating vision. He mentioned episodic unusual feeling in his legs with episodes during which he was not able to walk normally. MRI of the entire spine with contrast showed diffuse leptomeningeal enhancement involving the entire spine, worse at the lumbar and sacral levels, where there was circumferential thickened leptomeningeal enhancing soft tissue occupying the thecal sac. Repeat brain MRI with contrast showed mild leptomeningeal enhancement at the skullbase. The patient was admitted to the hospital and a biopsy of the mass at the L2 level was performed via posterior laminectomy. Pathology showed a leptomeningeal melanocytic neoplasm, consistent with a malignant melanoma.1 He had no prior skin melanoma and repeat CT of chest/abdomen/pelvis was normal. Molecular studies were negative for BRAF, GNAQ and GNA11 mutations,2 but showed alteration in the RIPK1 gene which has been recently described as a driver in melanoma.