Diagnosis of mediastinal lesions unassociated with lung carcinoma diagnosed by endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA)

Abstract

Endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) is a safe, cost-effective, and accurate diagnostic modality for the lung/mediastinum. Although some studies have been published on EBUS-TBNA of isolated mediastinal lesions, none have been reported from the United States. This study examines EBUS-TBNA for diagnosis of isolated mediastinal lesions. All cases of mediastinal EBUS-TBNA (defined in radioanatomic terms) during a 7-year period (July 2007-September 2014) were obtained from the anatomic pathology database. Pathologic reports, clinical notes, bronchoscopy notes, and imaging studies were reviewed. Only patients with a mediastinal lesion or non-pulmonary parenchyma-based lesions sampled by EBUS-TBNA without a prior or synchronous lung carcinoma were included in this study. Of the 3005 EBUS-TBNA cases accessioned during this time period at our institute, 47 fulfilled the inclusion criteria. The median patient age was 61 years (range: 27-84 years). Both genders were nearly equally represented. A definitive cytologic interpretation was rendered in 40 out of 47 cases (85.1%). Malignancies included non-pulmonary carcinomas (8), sarcomas (5), hematolymphoid malignancies (5), neuroendocrine neoplasm (1), melanoma (1), and undifferentiated malignancy (1). Surgical follow-up was available in 18 of 47 cases (38.3%). There was cytologic-histologic correlation in 16 of 18 cases (88.9%). Surgical follow-up of all cysts diagnosed by cytology were benign cysts. Over the 7-year period, an increasing proportion of all EBUS-TBNAs performed were for mediastinal lesions unassociated with lung carcinoma. EBUS-TBNA has a high accuracy rate when used to diagnose mediastinal lesions unassociated with lung carcinoma. Its utility as a primary diagnostic modality in this setting needs to be explored further.