Although initially responsive to cytoreductive surgery and platinum- and/or taxane-based chemotherapy, a majority of patients with epithelial ovarian cancer, cancer of the fallopian tube or the peritoneum will eventually relapse. Recurrence within 6 months after completing platinum-containing chemotherapy indicates a platinum-refractory cancer disease. New therapeutic strategies are required in platinum-refractory disease. Inhibition of growth signals induced by the epidermal growth factor receptor pathway, or by the estrogen receptor pathway provides promising targets in epithelial ovarian cancer, cancer of the fallopian tube or the peritoneum. The trial is to evaluate the safety and tolerability of the combination of the epidermal growth facto tyrosine kinase inhibitor ZD1839 and the clinically established antiestrogen tamoxifen.