Retrospective Study of 48 Cases of Primary Central Nervous System Lymphoma (PCNSL) (P6.287)

Objective: To evaluate immunologic status, clinical presentation, cerebrospinal fluid (CSF) examination, brain magnetic resonance imagining (MRI) and histopathology from adult patients with Primary Central Nervous System Lymphoma (PCNSL) Background: PCNSL is a rare and infrequent form of non-Hodgkin lymphoma restricted to the Central Nervous System. More than 90[percnt] to the PCNSL are B-cell type and affect patients between 50-70 years old. The most important risk factor associated with the development of PCNSL is immunodeficiency Methods: We enlisted retrospective 48 cases in our center with PCNSL from January 1992 to May 2015. Data was collected from clinical records according to the objectives. Results: Forty-eight cases of PCNSL were found in clinical records with median age at diagnosis of 61 years old (range 25-81); it was more frequent in males (2.1:1). Seventy-nine percent were immunocompetent patients. Pyramidal syndrome was the main initial clinical manifestation (56[percnt]). Regarding brain MRI findings 92[percnt] had parenchymal involvement (43[percnt] with frontal lobe compromise), 9[percnt] had meningeal involvement and 1[percnt] had ophthalmic involvement at diagnosis. Restricted signal on Diffusion Weighted Imaging was found on MRI of 18 patients and contrast enhanced lesions were found in 28 patients. In 17 patients CSF studies were performed, 76[percnt] had abnormal findings and in only 11.8[percnt] positive cytology results were detected. The most frequent type was diffuse non-Hodgkin lymphoma (80[percnt]), being B-cell type the most common form between them (96[percnt]). Conclusions: In our series PCNSL was more frequent in elderly patients and males. Our population showed high frequency of immunocompetent patients. At initial evaluation, clinical manifestations and MRI findings were variable. Early recognition and diagnosis of this entity allows for a prompt treatment, thus preventing empiric therapeutic interventions that may mislead and delay diagnosis. Disclosure: Dr. Alessandro has nothing to disclose. Dr. Pastor Rueda has nothing to disclose. Dr. Carpani has nothing to disclose. Dr. Blaquier has nothing to disclose. Dr. Tognarelli has nothing to disclose. Dr. Varela has nothing to disclose. Dr. Arakaki has nothing to disclose. Dr. Diez has nothing to disclose. Dr. Muggeri has nothing to disclose.