CT-guided transthoracic needle biopsy in the diagnosis of sarcoidosis

In patients with suspected sarcoidosis requiring pathologic confirmation of the presence of noncaseating granulomatous inflammation and the exclusion of alternative disorders, bronchoscopic transbronchial lung biopsy and more recently transbronchial needle aspiration of mediastinal lymph nodes have been the standard biopsy procedures in most cases. We describe our experience with computed tomography-guided transthoracic needle biopsy (CT-TNB) of mediastinal lymph nodes for the diagnosis of sarcoidosis.

We retrospectively reviewed our single institution experience with coaxial CT-TNB of enlarged mediastinal lymph nodes in the diagnosis of sarcoidosis. Forty-one biopsies were performed in 40 patients over a 10-year period from 1997 to 2007. Final pathologic diagnosis was obtained from record review. The type of biopsy performed (aspiration cytology, core needle biopsy for histology, or both) was recorded. The method of needle approach used was obtained from review of images obtained during biopsy and the radiology report. Complications including pneumothorax, bleeding, and need for chest tube insertion for pneumothorax drainage were recorded. Yield of cytologic versus histologic diagnosis of sarcoidosis was compared using a Fisher exact test.

Overall diagnostic yield was 93%, with core needle biopsy having a significantly higher yield as compared with fine needle aspiration cytology (96% vs. 78%, P<0.05). Pneumothorax developed in 22%, with 5% requiring overnight catheter drainage.

CT-TNB is a safe and accurate technique in the pathologic diagnosis of sarcoidosis, particularly when core tissue specimens are obtained.