OUTLINE: This is randomized, multicenter study. Patients are stratified according to gender, liver metastases (yes vs no), and duration of response to prior chemotherapy (6 months or less vs greater than 6 months). Patients are randomized to one of two treatment arms. Arm I: Patients receive topotecan IV over 30 minutes on days 1-5. Arm II: Patients receive topotecan orally on days 1-5. Treatment repeats every 3 weeks in the absence of unacceptable toxicity. Patients experiencing complete or partial response continue until progression or for at least 2 courses past maximal response. Patients with stable disease should receive at least 4 courses. Quality of life is assessed Patients are followed every 3 months.