[Anastrozole-resistant breast cancer responsive to exemestane--a case report].

We describe a postmenopausal woman suffering from advanced breast cancer with pleural effusion. She had prior anastrozole therapy, and was referred to our hospital with dyspnea. The use of exemestane, a highly selective steroidal aromatase inhibitor (25 mg daily), successfully induced remission of pleural effusion. Exemestane is a useful treatment for postmenopausal woman with advanced breast cancer, which is refractory to anastrozole.