EBUS-TBNA vs Flex 19G EBUS-TBNA

Endobronchial Ultrasound Transbronchial Needle Aspiration (EBUS-TBNA) Versus Flexible 19G Endobronchial Ultrasound Transbronchial Needle (Flex 19G EBUS-TBNA) in the Assessment of Mediastinal and Hilar Lymphadenopathy: a Randomised Trial

Endobronchial ultrasound (EBUS) guided transbronchial needle aspiration (EBUS-TBNA) is an excellent tool for sampling enlarged mediastinal and hilar lymph nodes, but only provides needle aspirate samples which are often adequate for cytological examination only. More advanced histopathological and immunocytopathological assessment of tissue samples, which is particularly important in the diagnosis and staging of cancer, is often not possible with the small cellular samples obtained by EBUS-TBNA. A new transbronchial nodal aspiration needle (the Flex 19G EBUS-TBNA needle) has been developed with a larger needle diameter and more flexibility at the distal end, allowing better access to some lymph nodes stations. This needle can be passed down an EBUS scope and can hypothetically circumvent the deficiencies of EBUS-TBNA highlighted above by providing tissue adequate for histological assessment rather than cytological assessment alone. This study aims to establish whether the use of the Flex 19G EBUS-TBNA needle can improve the diagnostic yield of EBUS sampling procedures compared to the use of the conventional TBNA needle, thereby allowing more accurate diagnoses and reducing the need repeat procedures or more invasive surgical biopsies, without causing an increase in complication rates. Patients with enlarged mediastinal and hilar lymph nodes referred for EBUS-TBNA will be randomised to have their nodes sampled by either the EBUS-TBNA needle (conventional procedure) or the novel Flex 19G EBUS-TBNA needle. The investigators hope to recruit 250 patients over a 24 month period.

The difference in quality of diagnostic tissue obtained between the two study arms following 4 separate needle punctures per lymph node

Both specimens (cell pellet and tissue fragments) will be assessed by means of a semiquantitative assessment of material (normal lymph node or lesional tissue) present using the formal scoring system described by Mair.

The difference between the two study arms in the percentage of lymph nodes sampled where enough tissue is obtained for complete immunohistochemical and genetic mutation analysis.

The difference between the two study arms in yield (quantity of diagnostic material) in patients ultimately diagnosed with sarcoidosis

The difference between the two study arms in yield (quantity of diagnostic material) in patients ultimately diagnosed with lymphoma

Inclusion Criteria: Scheduled for EBUS-TBNA as part of clinical care Lymph nodes larger than 10mm in diameter Age > 18 years Written informed consent Exclusion Criteria: Contraindication to needle biopsy (e.g. coagulopathy, anticoagulation, thrombocytopenia) Inability to obtain informed consent