Effect of antiviral drugs used to treat cytomegalovirus end-organ disease on subsequent course of previously diagnosed Kaposi's sarcoma in patients with AIDS

Objective: To evaluate the association of ganciclovir (GCV) and foscarnet ( PFA) therapy with the outcome of previously diagnosed Kaposi's sarcoma (KS) after initiating antiviral therapy for cytomegalovirus (CMV) end-organ dis ease. Design: Retrospective study. Methods: KS progression was defined as a clinically obvious increase in siz e of baseline cutaneous or mucosal lesions, a new diagnosis of visceral KS, or initiation of a new systemic antineoplastic regimen or radiation therap y to treat KS. Multivariate analyses of risk of KS progression were calcula ted for prior duration of KS before initiating CMV treatment, treatment wit h PFA or GCV, number of weeks treated with PFA or GCV, absolute CD4 lymphoc yte count at time of CMV-related disease diagnosis, diagnosis of KS prior t o 1991, visceral KS, prior systemic chemotherapy, and prior radiation thera py. Results: Among 66 patients who received greater than or equal to 14 days PF A (N = 20) or only GCV (N = 46), median time to progression of KS was 211 d ays (95% confidence interval [CI], 46-578) for patients who received PFA ve rsus 22 days (95% CI, 15-41) for those who received only GCV (p < .001). In the stepwise multivariate analysis, only prior visceral KS (rate ratio [RR ] = 2.80; 95% CI, 1.07-7.35) and foscarnet therapy (RR = 0.24; 95% CI. 0.11 -0.53) were significantly associated with risk of KS progression. Conclusion: PFA may be an effective therapy for AIDS-related KS; prospectiv e trials are indicated.