CT pattern of lymphadenopathy in untreated patients undergoing bronchoscopy for suspected sarcoidosis

SummaryBackground and objectiveTransbronchial needle aspiration procedures (TBNA, EBUS-TBNA) in sarcoidosis are associated with better results in stage I, and are preferentially performed in three lymph node stations (4R, 7, 11) as well as in the right mediastinal stations. We hypothesized that CT characteristics of lymphadenopathy, which were never systematically evaluated in untreated patients undergoing bronchoscopy for suspected sarcoidosis, could help explain the pattern of sampling and the different yield by radiographic stage of TBNA and EBUS-TBNA.MethodsNumber, size and location of lymph nodes were recorded in 74 consecutive sarcoidosis patients referred for biopsy, and were correlated with the radiographic stage.ResultsThe mean number of stations harboring enlarged nodes was 8.05 per patient. Lymphadenopathy was more common in stations 7 (98.6% of patients), 11R (97.3%), 11L (86.5%), and 4R (79.7%). The overall mean size was 14.39 mm, but the largest mean size was documented in stations 7 (17.57 mm), 11R (16.83 mm), 8R (16.02 mm), and 4R (15.19 mm). The median [IQR] number of enlarged lymph node stations was significantly higher in the right than in the left mediastinum (2 [1–2] versus 0 [0–1], p < 0.001). No relationship was found between lymphadenopathy and sarcoidosis stage.ConclusionsThe CT pattern of thoracic lymphadenopathy helps explain the excellent yield and the pattern of sampling of TBNA and EBUS-TBNA in sarcoidosis, but does not explain the higher yield associated with these procedures in stage I.