Successful diagnosis of a combined thymic epithelial tumor by endobronchial ultrasound-guided transbronchial needle aspiration.

INTRODUCTION: Endobronchial ultrasound-guided tranbronchial needle aspiration (EBUS-TBNA) can be applied to not only the determination of the clinical stages of lung cancer, but also the diagnosis of lymphadenopathies such as lymphoma and sarcoidosis.

CASE REPORT: We report the successful diagnosis of a combined thymic epithelial tumor in a 68-year-old female by EBUS-TBNA. The patient presented with a 6-month history of dysesthesia in bilateral legs. Chest computed tomography revealed a 5.5 cm-tumor with heterogeneous enhancement in the superior and anterior mediastinum. The serum levels of ProGRP and NSE were elevated and anti-Hu antibody was positive at the time of diagnosis. A biopsy by EBUS-TBNA revealed histological evidence of a combined thymic epithelial tumor consisting of small cell neuroendocrine carcinoma and thymic carcinoma. Chemo-radiotherapy reduced the tumor remarkably in size, but the patient's neurologic symptoms remained.

CONCLUSION: This case suggests that EBUS-TBNA is a safe and useful technique for the diagnosis of paratracheal mediastinal tumors.