Percutaneous fine-needle aspiration biopsy of mediastinal lesions.

Percutaneous fine-needle aspiration biopsy (PNAB) of mediastinal masses was carried out in 116 patients. The technique yielded a high percentage of correct diagnoses, and the results were usually available within hours. More importantly, the procedure was well tolerated by patients, and in this series of 116 cases, only one serious complication was encountered. There was a high accuracy (90.3%) in the cytologic diagnosis of mediastinal metastases from lung and extrathoracic sites. Excellent results were also achieved with the cytologic diagnosis of thymoma (82.4%). Very good results were achieved with benign mediastinal cysts, and PNAB with aspiration of fluid proved to be a valuable tool in the diagnosis of these lesions. The results achieved with the cytologic diagnosis of lymphoma supported by pathology (66.7%) and with neurogenic tumors were acceptable, but less impressive.