Immunoblastic Lymphoma in Persons with AIDS-Associated Kaposi's Sarcoma: a Role for Kaposi's Sarcoma|[ndash]|Associated Herpesvirus

摘要

Kaposi's sarcoma–associated herpesvirus, the viral agent of Kaposi's sarcoma, is associated with two lymphoproliferative disorders: primary effusion lymphoma and multicentric Castleman's disease. To identify other lymphoproliferative conditions linked with Kaposi's sarcoma–associated herpesvirus, we studied non-Hodgkin's lymphomas arising in individuals with AIDS-associated Kaposi's sarcoma. Formalin-fixed tissues from 24 such lymphomas were examined. As expected, two primary effusion lymphomas were Kaposi's sarcoma–associated herpesvirus–positive, with immunohistochemistry demonstrating the Kaposi's sarcoma–associated herpesvirus latency-associated nuclear antigen in the nuclei of all neoplastic cells. Additionally, three of seven evaluable cases of the immunoblastic variant of diffuse large B-cell lymphoma (immunoblastic lymphoma) showed similar latency-associated nuclear antigen staining. These Kaposi's sarcoma–associated herpesvirus–positive immunoblastic lymphomas resembled primary effusion lymphoma histologically but were not known to involve body cavities (sites included lymph nodes, soft tissues of the neck, and spleen). Notably, 5–20% of the neoplastic cells in the Kaposi's sarcoma–associated herpesvirus–positive immunoblastic lymphomas also showed cytoplasmic staining for viral interleukin-6, a biologically active cytokine homologue found in primary effusion lymphoma. We conclude that Kaposi's sarcoma–associated herpesvirus is present in some immunoblastic lymphomas in persons with AIDS-associated Kaposi's sarcoma.