Abstract
BACKGROUND: Visual impairment in Primary CNS lymphoma (PCNSL) in most of the cases is due to an intraocular lymphomatous involvement, especially uveitis. Optic nerve infiltration (ONI) in PCNSL is a rare condition. We sought to describe its clinical presentation, imaging characteristics, and outcomes. METHODS: Patients with ONI of PCNSL were retrospectively identified from 1998 to 2014 from the databases of the university hospitals Pitié-Salpêtrière (Paris) and René Huguenin (Saint-Cloud), and the academic teaching hospital Pasteur (Colmar), France. Exclusion criteria were intraocular involvement, orbital lymphoma, or other systemic lymphoma. Clinical presentation, neuroimaging, biological features, treatment and outcomes were assessed from their medical records. RESULTS: Only 6 of 710 PCNSL were identified as presenting ONI. Patients' median age at presentation was 65 years (49-78), 5 were women. 2 patients had ONI at initial diagnosis, 3 at 1st relapse after HD-MTX based chemotherapy, and 1 at 2nd relapse after HD-MTX, salvage chemotherapy and high-dose chemotherapy with autologous stem cell transplant. Clinical presentation: Rapidly progressive visual impairment without red eyes (6/6 patients), painless (4/6), unilateral (4/6), bilateral (2/6), bilateral hemianopia (2/6). MRI: Optic nerve swelling (3/6), contrast-enhancement of the entire ON (5/6) or of the ON sheath (1/6); Localization of ONI: Chiasmic (3/6), cisternal (3/6), intracanalicular (3/6), and intraorbital (4/6). Additional CNS lesions were seen in 4/6. Systemic lymphoma was excluded in all patients; lumbar puncture was done in 4/6 proving leptomeningeal disease in 2. Median delay from symptom onset to treatment: 25 days (10-140). Treatment: Different chemotherapy regimens were administered but lymphoma recurred in the majority. Clinical outcome: Partial recovery (2/6 patients), persisting low vision or blindness (4/6). Radiological outcome: Complete remission (4/6), partial remission (1/6), stable disease (1/6). Median PFS after ONI: 11 months (3-11), OS: 32 months (12-40). CONCLUSIONS: Intraocular involvement is observed in about 15% of PCNSL, clinically marked by slowly progressive visual deterioration over several months, usually caused by posterior uveitis. Lymphomatous infiltration of the optic nerve is characterized by a rapidly progressive severe visual impairment. In patients with ONI as initial presentation of PCNSL, it is difficult to establish the diagnoses as differential diagnosis are broad. In these patients, optic nerve biopsy should be discussed only in absence of cerebral lesions. At relapse, clinical presentation, neuroimaging and the absence of intraocular involvement may help to establish the diagnosis. As optic nerve functional outcome is poor, rapid treatment might improve clinical outcome. ACKNOWLEDGEMENTS: LOC national network (INCa)