Background: Evidence regarding the utility of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the assessment of isolated mediastinal lymphadenopathy (IMLN) is evolving. Its diagnostic accuracy in the evaluation of suspected lymphoma remains uncertain.
Methods: We reviewed a prospectively recorded database of consecutive patients with suspected lymphoma who underwent EBUSTBNA to evaluate IMLN. Patients in whom EBUS-TBNA was nondiagnostic subsequently underwent surgical biopsy or a minimum of 6 months radiologic surveillance.
Results: Ninety-eight patients underwent EBUS-TBNA for evaluation of IMLN. Clinicoradiologic features suggested sarcoidosis as the likely diagnosis in 43 patients. In the remaining 55 patients, EBUS-TBNA achieved definitive diagnosis in 42 patients (76%; 95% confidence interval [CI] 55-90). Lymphoma was ultimately diagnosed in 21 of 55 patients (38%). EBUS-TBNA demonstrated lymphoma in 16 (76%) patients; however, four patients required further surgical biopsy to completely characterize lymphoma subtypes. Surgical biopsy was required to diagnose specific lymphoma subtypes not readily amenable to diagnosis with low volume specimens. Sensitivity and specificity for definitive diagnosis of lymphoma were 57% (95% CI 37-76) and 100% (95% CI 91-100), respectively.
Conclusions: Although the diagnostic accuracy of EBUS-TBNA for lymphoma is lower than that for the lung cancer staging, the procedure is an appropriate investigative technique for the patients with IMLN because of the low incidence of lymphoma in this population, and the significant proportion of such patients (76%) in whom surgical biopsy is obviated.