Diagnostic implication of Kaposi's sarcoma-associated herpesvirus with special reference to the distinction between spindle cell hemangioendothelioma and Kaposi's sarcoma.

Abstract

To assess the diagnostic utility of recently identified Kaposi's sarcoma-associated herpesvirus (KSHV, also referred to as human herpesvirus 8) in distinction between Kaposi's sarcoma (KS) and other types of vascular lesion, especially spindle cell hemangioendothelioma (SCH). We conducted a polymerase chain reaction analysis of KSHV in 93 cases of benign and malignant vascular lesions, using DNA extracted from archival specimens. All five cases of Kaposi's sarcoma examined, including cases related and cases unrelated to acquired immunodeficiency syndrome, were positive for KSHV. Vascular lesions other than KS, including 6 SCH, 1 kaposiform hemangioendothelioma, 8 angiosarcomas, 46 hemangiomas (15 cavernous, 12 capillary, 7 venous, 6 intramuscular, 2 sinusoidal, 2 epithelioid, 1 microvenular, 1 glomeruloid), and 7 glomus tumors were consistently negative, except for 1 of the 20 pyogenic granulomas examined. Our data support the previous finding that KSHV is confined almost exclusively to KS, irrespective of human immunodeficiency virus infection, and suggest that KSHV is a reliable diagnostic marker to differentiate KS from other vascular lesions, including those with KS-like morphology, such as SCH.