A cohort of 61 patients with Kaposi's sarcoma (KS) and AIDS was seen in the Oncology Unit of the Toronto General Hospital between 1982 and 1986. In an attempt to identify prognostic variables, laboratory and clinical parameters were examined using Kaplan-Meier estimates and the Cox Regression Model. All patients were male, median age 36 years (range 23-52). In 49 patients KS was diagnosed before any AIDS-associated opportunistic infection (OI). Three patients had concurrent KS and OI, and nine patients developed KS one or more months after an OI. Only 11 patients had stage I or II disease, 34 stage III, and 15 stage IV. Only 18 patients (30%) were asymptomatic. Twenty-six percent had fever, night sweats, or weight loss, 11% had minor opportunistic infections, and 33% had both symptom complexes. The median overall survival was 10.5 months. The survival of patients who received chemotherapy for their KS was not significantly different from the survival of non-treated patients (p = 0.7). Although significant differences in survival could not be seen between stages, patients with both systemic symptoms and minor opportunistic infections had significantly shorter survival (p = 0.03). Survival from the onset of KS was significantly shorter for patients who had experienced a previous OI, but their overall survival from the date of diagnosis of AIDS was not significantly different from those patients presenting with KS alone. When analyzed separately the laboratory parameters of hemoglobin (p less than 0.0001), absolute lymphocyte count (p = 0.03), platelet count (p = 0.04), and T4 level (p = 0.05) demonstrated a significant relationship with survival.(ABSTRACT TRUNCATED AT 250 WORDS)