Cytotoxic chemotherapy

Cytotoxic chemotherapy is a form of treatment given by injection into a vein. These treatments poison fast-growing cells, like KS cells, more than normal cells. However, they can also affect other cells in the body that normally grow quickly, in the bone marrow, hair follicles and the gut, causing anaemia, immune damage, hair loss and diarrhoea. Different chemotherapy drugs cause slightly different side-effects, so a cytotoxic chemotherapy regimen is tailor-made for each person. For example, if someone already had bone marrow damage from AZT, it would be better to use a drug like vincristine, which causes less marrow damage.

Before the advent of liposomal chemotherapy, treatment usually consisted of a combination of three or more different drugs. Cytotoxic drugs include bleomycin, doxorubicin, etoposide (Etopophos / Vepecid), tenoposide, vinblastine and vincristine. They are somewhat effective, but after a period of time their effect may diminish and the KS may progress. Vinorelbine (Navelbine) is a newer chemotherapy drug now being tested in trials.

Paclitaxel (Taxol) has been licensed in the United States for the second-line treatment of KS. In the United Kingdom it is approved for treating certain forms of ovarian cancer. It has been shown to have a 59% response rate and studies directly comparing paclitaxel and doxorubicin are ongoing.

It is important to take Pneumocystis pneumonia (PCP) prophylaxis while receiving chemotherapy, because the treatment causes immunosuppression and increases the risk of opportunistic infections.