KAPOSIS SARCOMA-ASSOCIATED HERPESVIRUS DNA-SEQUENCES IN AIDS-RELATED AND AIDS-UNRELATED LYMPHOMATOUS EFFUSIONS

Primary effusions presenting as the sole lymphoma localization are als o known as body-cavity-based-lymphoma (BCBL), and have been shown to c arry Kaposi's sarcoma herpesvirus (KSHV) DNA sequences. The aim of thi s study was a comparative analysis of the clinical, pathologic and mol ecular features of BCBL and lymphomatous effusions secondary to tissue -based lymphomas occurring both in the general population and in HIV-1 -infected individuals, All the lymphomatous effusion samples (seven AI DS-related and nine AIDS-unrelated) were subjected to an identical mul tiparameter investigation, including collection of clinical data, anal ysis of morphology and immunophenotype, as well as the study of viral sequences and genetic lesions. In six cases defined as BCBL (four AIDS -related and two AIDS-unrelated), the patients exhibited exclusive or predominant involvement of the body cavities. BCBL tended to display i ndeterminate phenotypes (4/6), whereas all AIDS-related and AIDS-unrel ated lymphomatous effusions secondary to tissue-based lymphomas consis tently expressed B-cell phenotype. Detection of KSHV DNA sequences was restricted to cases of BCBL (3/4 AIDS-related and 1/2 AIDS-unrelated) , whereas EBV association (3/4) and expression of EBV-encoded antigens (LMP-1, 2/3; EBNA-2, 1/3) were confined to the AIDS-related BCBL. Ove rall, our results confirm that both AIDS-related and AIDS-unrelated BC BL preferentially associate with peculiar clinical, immunophenotypic a nd molecular features among lymphomatous effusions and therefore shoul d be singled out as a specific clinico-pathologic entity.