Linfoma primário do sistema nervoso central

Abstract

Primary Central Nervous System lymphoma (PCNSL) is an extranodal non-Hodgkin lymphoma in the brain, leptomeninges, spinal cord or eyes. The incidence of PCNSL increased approximately three-fold in the last decades. Nowadays, it represents 0.4 case per 100,000 people and accounts for 4% of all primary brain tumors. Although individuals infected with HIV have a 3,600-fold increased risk of developing PCNSL compared with the general population, the incidence has not increased only in AIDS group. Recent data suggest that the incidence of PCNSL declined in the AIDS group after the introduction of anti-retroviral drugs. Around 90% of PCNSL cases are classified as diffuse large B-cell lymphoma, 10% involve the eyes and 10% of patients are HIV positive. The clinical presentation depends on the location of the tumor with neurological rather than systemic symptoms. Computed tomography (CT) and magnetic resonance imaging (RMI) are essential in diagnosis, however the gold standard is tumor biopsy. Staging should be made with imaging and bilateral biopsy of bone marrow. The main poor prognosic parameters are performance status greater than 1, age older than 60 years, elevated DHL, high liquor protein concentration and tumor located within the deep regions of the brain. BCL-6 expression identified in the tumor confers a better prognosis. Currently, a combined therapy with high doses of methotrexate and whole-brain radiotherapy is the therapy of choice. Nowever, wholebrain radiotherapy should be carefully analyzed because neurotoxity is a frequent problem in the elderly and in relapsed and refractory patients.