The evaluation of human herpesvirus 8 (Kaposi's sarcoma-associated herpesvirus) in cutaneous lesions of Kaposi's sarcoma: a study of formalin-fixed paraffin-embedded tissue.

The etiologic role of human herpesvirus 8 (HHV8) in Kaposi's sarcoma (KS) remains controversial. This polymerase chain reaction (PCR)-based study was undertaken to evaluate the relationship of HHV8 in KS from our geographical region and to determine its utility in formalin-fixed, paraffin-embedded biopsy specimens. Forty-two biopsy specimens were studied, including nine AIDS-associated cases and four from classic KS. Of the 39 patients included, 21 were HIV+ and 18 had no clinical evidence of HIV infection. Only a single (internal) primer pair was used in the PCR. All PCR products were tested with an HHV8 specific probe by dot blot analysis. Seven of the nine AIDS KS specimens were positive for HHV8 on electrophoresis, and all nine were positive after dot blot. Two of four specimens from classic KS were positive for HHV8 on the gel electrophoresis, and three of four were positive on blot confirmation. Non-KS specimens from 15 HIV+ patients yielded one positive venous hemangioma from a man with HHV8-positive KS at another site. Specimens from HIV-unrelated controls with a variety of diagnoses were negative by PCR with blot. The predominant negativity for HHV8 in non-KS lesions suggests that HHV8 is not widespread in our patients. These results demonstrate yet another series linking KS with HHV8 and show that paraffin-embedded biopsy specimens are satisfactory for this technique.