Kaposi's sarcoma

Since the discovery of its association with human immunodeficiency virus infection, Kaposi's sarcoma (1) has remained one of the most puzzling entities in the cutaneous repertoire of patients infected with HIV. An exhausting array of potential aetiological agents has been proposed.1 Until recently, even the basic categorisation of the condition (malignancy, reactive process, infection) has remained uncertain. Reports of Kaposi's sarcoma in homosexual men negative for HIV,2 coupled with the observation that among patients positive for HIV Kaposi's sarcoma was more common in homosexual men than in injecting drug users,3 led to the suspicion that the condition was sexually transmitted, presumably by a virus distinct from but often transmitted with HIV.

During the past year, several reports have emerged documenting the discovery of herpesvirus-like DNA sequences within Kaposi's sarcoma lesions.4 5 6 The DNA sequences (sometimes referred to as KS330(233) or KSHV) have been identified by polymerase chain reaction and by Southern blot hybridisation. These bits of DNA have been discovered in tissue from the lesions of patients with epidemic (HIV associated) Kaposi's sarcoma as well as classic Kaposi's sarcoma (on the legs of immunocompetent elderly men of Mediterranean descent) and African endemic Kaposi's sarcoma.5 The additional finding of similar sequences in tissue from some lymphomas in patients infected with HIV7 and in Kaposi's sarcoma from homosexual men negative for HIV6 lends support to the hypothesis that a novel group of …