PB1794 EXTRANODAL NK/T CELL LYMPHOMA NASAL TYPE, A TERCIARY CENTER EXPERIENCE IN CENTRAL MEXICO
Authors: A. Cuevas‐Juarez, G.I. Barranco‐Lampon, C. Ramos‐Peñafiel, E. Montaño‐Figueroa, J.J. Kassack‐Ipiña, J.F. Zazueta Pozos
Journal: HemaSphere (2019)

Background: Extranodal NK/T‐cell lymphoma (ENKTL) nasal type, is relatively rare, although the incidence has risen over the past century, the frequency varies in different geographic regions and racial populations, representing only 10–15% of all non‐Hodgkin lymphomas. It is usually clinically aggressive, originating from post‐thymic T‐lymphocytes and NK‐cells Aims: Our interest in ENKTCL nasal type is due to the prevalence of this entity in Mexico, which is comparable to that of countries with the most cases reported. This study aims to report our experience with ENKTCL nasal type, their main clinical and analytical characteristics and the impact they may have on response in a third level reference hospital in central Mexico Methods: A retrospective observational study was conducted, we collected all cases of patients with histopathological diagnosis of extranodal NK/T cell lymphoma nasal type from January 2013 to January 2019 in an attempt to examine clinical and analytical features, 56 patients were included. Data on clinical history, physical examination, performance status, baseline hematological and biochemical parameters, histology, imaging and bone marrow studies were collected from the computer database. The study included biopsy/excision material of patients registered within the hospital. Treatment records and responses were collected Results: Information was obtained from 56 patients (30 men, 26 women) with a mean age of 39.6 years (16‐78 years); 58.9% of patients had B symptoms, in 57% some infection was identified, 7% had some hemorrhagic event, none of the patients had thrombotic manifestations, 3.6% were identified with infiltration to bone marrow, in 7.1% patients CNS infiltration was identified through cytological analisis, 69.6% presented with early clinical stages, all this at the time of diagnosis. Regimens that included L‐Asparginase were administered to 28 patients (50%), 5 did not receive treatment due to early mortality related to the disease and the rest received CHOP‐like regimens, 67.7% received radiochemotherapy as first line treatment. Median overall survival was 6 years. In the univariate analysis of prognostic factors, it was identified that hemoglobin less than 10 gr/dL (p &lt; 0.01) and albumin less than 3.4 gr/dL (p &lt; 0.02) had an impact on survival. No difference was observed in overall survival (OS) based on the received chemotherapy regimen, we did however observed OS was better in those who received concomitant radiotherapy with the first‐line regimen (p &lt; 0.05). Summary/Conclusion: Extranodal nasal T‐cell / NK cell lymphoma is a relatively common neoplasm in Mexico, it is aggressive and with a high mortality. Our study did identify differences in overall survival in terms of some readily available tests, and since Mexico is a region with a higher prevalence in this type of lymphoma, more and better epidemiological and translational studies would be beneficial in our understanding of this entitiy in order to identify prognostic factors and potential therapeutic targets image