Magnetic resonance as initial screening diagnosis of secondary involvement of central nervous system in NHL diffuse large B cell lymphoma

Background: Central Nervous System (CNS) relapse in Diffuse Large B-cell Lymphoma occurs mostly 6-8 months after disease onset. This has led to propose that CNS infiltration is an early event in the evolution of the disease. We intend to evaluate the role of magnetic resonance imaging (MR) at diagnosis to detect early SNC compromise. Materials and Methods: Prospective longitudinal cohort’s study in DGCB patients treated at Hospital de Clínicas between 2013 and 2015. Skull MRI was performed in all patients at diagnosis and lumbar puncture was done according to predefined risk factors. Results: 35 patients were analyzed. Median age: 68 years (24-85 years). Stage III-IV: 62%, 57% good prognosis according to RIPI score and 43% poor prognosis. MRI was performed in all patients, with no pathological findings in any of them. Twenty-one patients fullfilled criteria for cerebrospinal fluid study. Twenty-two patients were studied and received intrathecal methotrexate prophylaxis. Meningeal relapse was observed in a single patient who had negative studies at diagnosis and had received complete prophylaxis at the end of the 6 R-CHOP series. Conclusions: Only one of the 35 patients relapsed in the CNS. This patient had a noral MRI and CSF study at diagnosis and had received prophylaxis with intrathecal chemotherapy. This results lead us to believe that the value of MRI to detect early infiltration in asymptomatic patients at diagnosis is low.