Plasmablastic Lymphomas – Immunophenotypic Spectrum and MYC Translocation.
Tanuja Shet, Sridhar Epari, Suhas Dhende, Manju Sengar, Reena Nair. Tata Memorial Hospital, Mumbai, Maharashtra, India
Background: Pathologists often face a problem of differentiating Plasmablastic lymphoma(PL) from diffuse large B cell lymphoma(DLBL) and plasma cell tumors even in HIV positive patients. This study was an attempt to categorise PL immunophenotypically using a panel of antibodies and also evalaute the incidence of MYC translocation recently reported in literature.
Design: The 102 PL studied were selected from a total of 249 AIDS related lymphomas accessioned at our institute. Immunohistochemistry was performed using the ABC technique and a wide panel of antibodies. We also evaluated a small number for the MYC translocation using the Vysis LSI IGH/MYC, CEP 8 tri-color, dual fusion translocation probe. Presence of Epstein Barr virus was assesed by using Novocastra EBER-ISH kit.
Results: Oral cavity was commonest site of presentation followed by cervical nodes, anorectum and soft tissue. All anorectal tumors occurred in homosexual men, while other patients had heterosexual behaviour. CD4 counts only in 17% were above 200. All tumors has plasmacytoid cells with 45 tumors showing myeloma like; 48 blastic and 9 with anaplastic morphology. The immunophenotypic expression is given in the Table.