Chemo-immunotherapy of advanced AIDS-related Kaposi's sarcoma

Kaposi's sarcoma (KS) is the most common neoplastic complication of HIV infection and AIDS. Multiple cytotoxic chemotherapy regimens have been used with various response rates. We have evaluated the efficacy and toxicity of low-dose chemotherapy in patients with poor-prognosis AIDS-related KS and the role of interferon alpha (IFN-alpha) in complete responders.

Twenty-five previously untreated patients with advanced KS received bleomycin (BL) 10 mg/m2 and vinblastine (VB) 6 mg/m2 on days 1 and 15 every two weeks. After six cycles, patients in complete remission received IFN-alpha (3 million U s.c. 3 times/week) combined with antiretroviral therapy. All patients were evaluated for toxicity using the World Health Organization (WHO) toxicity schedule. Both Eastern Cooperative Oncology Group (ECOG) and AIDS Clinical Trials Group (ACTG) response criteria were used to evaluate response and survival.

The overall response rate was 84% (95% confidence interval, 51-117%) with six complete remissions (24%) and 15 partial remissions (60%) by ECOG criteria, and 92% (95% confidence interval: 58-128%) with 17 partial remissions (68%) by ACTG criteria. The median duration of response on IFN-alpha treatment was 4.5 months (range, 2-10). The overall median survival duration for all 25 patients was 9 months (range 2-39). Grade 3-4 anemia was observed in five patients and grade 3-4 neutropenia in two patients. No other clinically significant (> or = grade 3) toxicities were observed.

Combination of BL and VB is effective and well tolerated, even if new therapeutic options are developing. This disease remains a challenging problem, so larger studies using the combination of chemotherapy and/or IFN-alpha with antiretroviral treatment are warranted.