A Study Evaluating the Diagnostic Yield and Safety of the ProCore vs Conventional EBUS-TBNA Needle in Subjects With Suspected Sarcoidosis

Sarcoidosis is a multisystem disorder of unknown cause characterized by granulomatous inflammation involving various organ systems. The diagnosis is made on the basis of a suggestive clinicoradiological picture, histopathologic evidence of non-caseating granuloma, and exclusion of other known causes for granulomatous inflammation. As the lung and mediastinal lymph nodes are the most commonly involved structures in sarcoidosis, various bronchoscopic techniques like endobronchial biopsy (EBB), transbronchial biopsy (TBLB) and transbronchial needle aspiration (TBNA) are needed for tissue sampling.

Among the bronchoscopic techniques, TBNA of lymph nodes is a useful modality especially when combined with endobronchial and transbronchial biopsies. The efficacy and safety of conventional TBNA are well established. With the advent of endobronchial ultrasound (EBUS) in the last decade, this new technology has been widely used to guide transbronchial needle aspiration. The technique is minimally invasive and offers the additional advantage of choosing the appropriate node for sampling based on the vascularity, echogenicity and size. Studies subsequently have demonstrated the superiority of EBUS-TBNA over conventional TBNA.

As EBUS-TBNA is the standard procedure now for accessing intrathoracic lymph nodes, the technical aspects of the procedure need further investigation. Several aspects have been studied to optimize the yield including the number of aspirations or passes required per lymph node station, needle gauge (21 vs. 22 gauge), suction pressure, and the distance travelled by the needle within the lymph node.

The EchoTip ProCore High Definition ultrasound biopsy needle (Cook Medical Inc., Bloomington, Ind., USA) is a novel needle that has been used mainly in sampling intra-abdominal lesions. It has a special bevel which allows a core biopsy along with aspiration of the lymph node material. In case of mediastinal lymph node enlargement due to malignancy, needle aspiration alone may yield sufficient material to identify malignant cells. However, in sarcoidosis, the core biopsy specimen obtained with the ProCore needle may potentially increase the identification of granulomas. The investigators hypothesize that the 22-gauge ProCore needle will have a higher yield in diagnosing intrathoracic lymphadenopathy due to sarcoidosis as compared to the conventional 22-gauge EBUS-TBNA needle. In this study, the investigators plan to evaluate the yield and safety of the 22-gauge ProCore needle as compared to the conventional 22-gauge EBUS-TBNA needle in patients with sarcoidosis.