Randomized Prospective Trial of EUS-FNA Versus EUS-FNB Using a Novel Core Biopsy Needle

Endoscopic ultrasound (EUS) is paramount in the diagnosis and evaluation of cancers involving the gastrointestinal tract. EUS allows for the acquisition of cellular (fine needle aspirate - FNA) or tissue biopsy (fine needle biopsy - FNB) for diagnostic purposes. This has traditionally been done with fine needle aspirate where a needle is inserted into the tumor and potentially malignant cells are extracted for microscopic analysis. More recently, a needle that allows a tissue biopsy for histologic analysis has been FDA approved. The Echotip Procore (Cook Medical) core biopsy needle (ETP), has been demonstrated to provide excellent efficacy for core biopsy samples. Final diagnostic yield using this needle ranges from 80-90% and appears to be significantly greater than EUS-FNA for lesions requiring histology for diagnosis. However, there is currently only limited data from prospective studies comparing EUS-FNA to EUS-FNB with the ETP needle. The investigators propose a randomized, prospective, cross-over study comparing diagnostic accuracy of EUS-FNA to EUS-FNB.