Trilostane therapy for advanced breast cancer.

Forty-one postmenopausal patients with advanced breast cancer have been treated with trilostane, a 3 beta D-hydrogenase delta 5-isomerase inhibitor, for periods of up to 1 year. One patient responded to trilostane and in six patients the disease was stabilized. The remaining patients failed to respond to therapy. Six patients who failed to respond to trilostane subsequently responded to other forms of endocrine therapy. It is concluded that trilostane alone is not a useful agent in the treatment of advanced breast cancer.