Efficacy of the Progesterone Receptor Antagonist Mifepristone for Palliative Therapy of Patients with a Variety of Advanced Cancer Types

Abstract

Background: Mifepristone has been demonstrated to improve longevity and quality of life in mice with spontaneous murine cancer without progesterone receptors and in human colon cancer. The present study evaluated the palliative effect of mifepristone in a variety of different types of human cancer. Patients and Methods: Mifepristone was given at 200 mg daily orally with permission from the Food and Drug Administration to people with widely metastatic human cancer no longer responsive to other chemotherapy regimens. Results: Improvement in pain and energy and/or length of life was found in thymic epithelial cell carcinoma, transitional cell carcinoma of the renal pelvis, leiomyosarcoma, pancreatic carcinoma, malignant fibrous histiocytoma and another case of adenocarcinoma of the colon. Conclusion: Our data demonstrate a palliative role for the use of mifepristone in cancer therapy. Progesterone receptor antagonists should be given a therapeutic trial in larger controlled studies of various malignancies in humans.