Plasmablastic Lymphoma : 12 Year Experience from a Single Center in Colombia -South America
Authors: Spirko Paola , José Enciso Olivera Leonardo , Otero Diana , Patiño Bonell , Acon-Solano Cristina , Alcala Sebastian , Valdes Jaime , Garces Andres , Martínez Cordero Humberto , Castillo Jorge J. 
Published: November 2020

Introduction:Plasmablastic lymphoma (PBL) is a rare high-grade lymphoma, in which the cells of origin have overlapping features between B cells and plasma cells. PBL has been associated with immunodeficiency states and Epstein Barr virus co-infection . The incidence of this disease among HIV negative patients is unknown, but the prognosis is poor, with a high relapse rate (60% in the first year of diagnosis) and a 5-year overall survival (OS) rate of less than 30%. Herein, we describe the clinical characteristics and treatment results of PBL patients in a tertiary cancer center in Colombia.
Methods:We identified patients older than 18 years with pathologically confirmed PBL, diagnosed from June 2007 to June 2019 . Electronic health records were review and clinical data, stage, laboratory results, immunodeficiency state, treatment and outcomes extracted by two researchers. Frequency and percentage were calculatedfor categorical variableswhilemeanand standard deviation (SD) or median and interquartile rangefor the continuous variables.Response was assessed using the Lugano criteria. OS was estimated using the Kaplan-Meir method.
Results:We identify 12 patient, of whom ten (83%) were male. The mean age at diagnosis was 40.5 years for men and 51.5 for women. Nine (75%) were HIV +. The mean age was 40 years and 57 years in HIV (-) and HIV (+) , respectively (p=0.31). All patients had advanced stage at diagnosis (Ann Arbor IIIB or IV), and the most frequent extranodal involved sites were anus, colon, and oral cavity. Bulky disease(&gt; 7.5 cms in the greatest diameter) were more common in the HIV + group (56% vs 33% in HIV- group). Immunophenotype was as expected, with no cases expressing CD20. Rates of expression of MUM1, CD38, CD79a and CD138 were 100%, 82%, 75% and 64% respectively. The median CD4 T-cell count in HIV+ patients was 143 cells/ul. EBER was available was positive in all cases evaluated. IPI scores were not available in all patients. Lactic dehydrogenase (LDH) was above the normal limit in all patients. The most frequent regimen used as the front line was EPOCH(66.7%). Other regimens included COEP(8.3%), DA-EPOCH(16.7%), R-EPOCH(8.3%). No patient received bortezomib. The response was complete in 55%, stable disease in 27% and progression in 18% of pacientes . With 40 months of follow-up time , the OS rate was 60%.
Conclusions:Our findings are similar to other series. In this population, PBL presents with advanced stage and extranodal involvement. Most patients were HIV (+) with a younger age at diagnosis in this group. The use of infusional regimens is associated with high response rates and possibly a superior OS , as compared with other series . The low number of patients included underscores the need for a multicentric registry of these cases.
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Disclosures
Castillo: Beigene:Consultancy, Research Funding;Abbvie:Research Funding;Kymera:Consultancy;Janssen:Consultancy, Research Funding;Pharmacyclics:Consultancy, Research Funding;TG Therapeutics:Research Funding.