Sarcoidosis is a granulomatous multisystem disorder most commonly involving the lungs. The identification of non-caseating granuloma without necrosis in biopsy-specimen obtained through flexible fibreoptic bronchoscopy helps to establish the diagnosis. Transbronchial lung biopsy (TBLB) has been the traditional method used to obtain lung tissue, however in recent reports transbronchial needle aspiration (TBNA) of lymphnodes has gained increasing popularity with reportedly greater diagnostic yield compared to TBLB particularly in stage 1 sarcoidosis. We wanted to compare the yield of both biopsy modalities.
We conducted a retrospective chart review analyzing the diagnostic yield from TBNA and TBLB in conjunction with radiographic staging based on chest x-ray and where available CT-scan in 32 patients with sarcoidosis diagnosed from 1996–2008. Rapid on-site evaluation (ROSE) was used to guide the choice of biopsy-mode/sites during bronchoscopy.
Overall, 29 out of 32 patients undergoing TBLB (90%) and 12 out of 19 patients undergoing TBNA (63%) had a diagnostic biopsy. TBLB was the sole diagnostic biopsy modality in 6 of 18 patients undergoing both TBLB and TBNA, whereas TBNA was diagnostic alone in only 1 of these 18 patients. In stage 1 the diagnostic yield was the same for both TBLB and TBNA (86%). In one case identification of granulomas by ROSE in tissue obtained through TBNA first obviated the need for TBLB.
The diagnostic yield of TBNA seems equal compared to TBLB in sarcoidosis stage 1 whereas in more advanced stages the yield of TBLB seems to exceed that of TBNA. However, TBNA is a useful first-line modality particularly in cases with easily accessible lymphnodes and in conjunction with ROSE (rapid on-site evaluation), thus reducing the risk of complications compared to TBLB. Further, with increasing operator experience for TBNA our yield might improve over time.
The choice of TBNA versus TBLB in the diagnosis of sarcoidosis should be guided individually based on radiographic staging, risks, operator experience, ROSE and other diagnostic considerations.
Markus Gutsche, No Financial Disclosure Information; No Product/Research Disclosure Information