Treatment Review #17 - March 1995
Kaposi's sarcoma (KS) is a type of cancer that can appear in
people with AIDS as dark brown or purple marks called lesions.
KS can also affect the internal organs. KS can be slow growing,
or indolent, but it can also be aggressive and grow very
rapidly. If it's aggressive, most people choose to start
Two Columbia University researchers recently announced there is
strong evidence that KS is actually caused by a newly
recognized herpes virus which they call KSHV. But demonstrating
that a virus causes a cancer is not an easy thing to do.
Herpesviruses have long been suspected as co-factors in HIV
disease, although before this no one has suggested that KS was
caused by any kind of virus. Herpesviruses are known to
sometimes tag along with HIV, and set up shop in a cell by
hanging out a welcome flag - the same sugar coated proteins
that HIV uses to enter into a cell.
Others feel that HIV infection itself may lead to the
development of this cancer. A group of scientists at San
Francisco General Hospital, UCSF, suggest that HIV causes the
body to produce chemicals that create a hospitable environment
for KS to grow.
Both of these groups of scientists could be right. In either
case, stopping the growth of KS is a priority. The drugs used
to treat KS at the present are not always effective, and they
are costly and toxic. Although a new drug, Doxil, has been
recommended for approval, there is debate about just how well
it works. Are the anti-herpes drugs foscarnet or acyclovir
effective against KS. Is the Abbott protease inhibitor a useful
KS treatment? Rapidly executed clinical trials - and agreement
on what a successful treatment works like - would at least give
us an idea.