Endobronchial Ultrasound-guided Transbronchial Needle Aspiration in the Diagnosis of Breast Cancer Thoracic Metastases and Detection of Receptor Discordance.

Background: Metastasis of breast cancer to mediastinal lymph nodes is common and biopsy of suspicious lesions can have important diagnostic, prognostic, and therapeutic implications, particularly with respect to tumor receptor status. Our aim was to show that endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) can be used for the diagnosis of metastatic breast cancer and demonstrate reliable receptor evaluation that can result in change of therapy.

Methods: A retrospective review of consecutive adult patients undergoing EBUS-TBNA from May 2007 to September 2012 was performed. Data collected for patients with a history of breast cancer included patient demographics, tumor pathology, receptor analysis, imaging, and bronchoscopy or surgical results.

Results: Sixty-four patients with a history of breast cancer aged from 31 to 81 years underwent EBUS-TBNA for the evaluation of mediastinal lymphadenopathy of which 16 patients had not been previously treated for their breast cancer with systemic therapy. Eighty suspicious lymph nodes were biopsied measuring 0.8 to 3.1 cm in diameter. Fifty-nine (92%) patients had diagnostic cytology for malignancy or benign lymphoid tissue. Breast malignancy was identified in 33 (52%) patients and 23 (70%) of these had sufficient samples for the evaluation of estrogen, progesterone, and human epidermal growth factor receptor 2 status. Overall 48% of the patients with receptors analyzed had discordance between the primary tumor and metastasis.

Conclusions: EBUS-TBNA is a useful tool for evaluating mediastinal lymphadenopathy in patients with a history of breast cancer and can provide information on the concordance of receptors status between the primary tumor and metastatic sites in the thorax.