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 disease.

Design: Retrospective study.

Methods: KS progression was defined as a clinically obvious increase in size of baseline cutaneous or mucosal lesions, a new diagnosis of visceral KS, or initiation of a new systemic antineoplastic regimen or radiation therapy to treat KS. Multivariate analyses of risk of KS progression were calculated for prior duration of KS before initiating CMV treatment, treatment with PFA or GCV, number of weeks treated with PFA or GCV, absolute CD4 lymphocyte count at time of CMV-related disease diagnosis, diagnosis of KS prior to 1991, visceral KS, prior systemic chemotherapy, and prior radiation therapy.

Results: Among 66 patients who received > or = 14 days PFA (N=20) or only GCV (N=46), median time to progression of KS was 211 days (95% confidence interval [CI], 46-578) for patients who received PFA versus 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; prospective trials are indicated.