Kaposi’s sarcoma (KS) represents a potential model for a virally associated human tumor. Prior to 1981, KS was considered a rare tumor occurring in cluster distribution. A sudden increase in the number of KS cases along with pneumonia caused by Pneumocystis carinii (PCP) and other opportunistic infections (01) was observed among the victims of the epidemic of acquired immune deficiency syndrome (AIDS). Initially, the cases were seen in New York and California, but now they have been reported from most large cities in the USA and many other countries. The first reports were exclusively among homosexual men and intravenous drug abusers; the disease, however, is now being observed among Haitians, hemophiliacs, and even in some children with AIDS.

In this new epidemic form, KS presents with a more aggressive course involving skin, gastrointestinal tract, and lymph nodes.’The epidemic form of KS has a similar course to lymphadenopathic KS seen in African children. Whereas 01 have been the major cause of death in this epidemic, cases have been seen in whom KS has spread rapidly to vital organs such as lung, liver, and spleen. Much interest has been generated in the study of KS since the epidemic of AIDS. It is hoped that investigative work will provide a better insight into this interesting tumor.