Pleural effusion in breast cancer. Thoracoscopy for hormone receptor determination.

Metastatic breast cancer frequently presents as a malignant pleural effusion. Knowledge of the estrogen and progesterone receptor status of the tumor predicts response to hormonal therapy, but breast cancer tissue in the pleural space is not readily accessible for hormone receptor determination. Thoracoscopy was used in six breast cancer patients with pleural effusions; all but one had concurrent sites of metastases. In five of six women recurrent breast cancer in the pleural cavity was diagnosed by thoracoscopy, and in four sufficient tissue was obtained for receptor assay. All patients achieved excellent control of their pleural effusions through a combination of local sclerotic measures and systemic therapy. Thoracoscopy is a safe procedure that can be performed under local anesthesia and is useful to visualize the pleural space, not only for diagnosis but also for obtaining breast cancer tissue for hormone receptor determination.