Six patient with malignant effusions (five with ascites and one with malignant pleural effusion) due to refractory ovarian carcinomatosis, received intracavitary injections of ovarian viral oncolysate (VO). Measurements were made of the intracavitary activities of T cell growth factor (TCGF-IL-2) and B cell growth factor 12-kD (BCGF) and these were correlated with the clinical activity and cytologic changes in the malignant effusions. Both BCGF and IL-2 activities were demonstrated in malignant effusions prior to therapy although these were relatively higher for BCGF. Increases in the activities of both lymphokines were observed in the post VO treatment samples ranging from 4.1% to 45.0% for BCGF and 4.8% - 33.9% for IL-2. One patient who exhibited marked clinical improvement accompanied by mononuclear cell infiltrates and diminution of ascitic fluid malignant cells, also had elevation of lymphokine activities after repeated VO injections. These data provide further support for the role of VO as inducers of regional immunity.