Since its initial description in 1992 (1), endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has become the procedure of choice to obtain samples to reach the definitive diagnosis and proper lymph nodal staging of lesions of the gastrointestinal (GI) tract and of adjacent organs (2). The sensitivity of EUS-FNA, however, is strongly dependent on the availability of an on-site cytopathology, which has been clearly demonstrated to significantly influence the diagnostic accuracy, as well as, the proportions of indeterminate and unsatisfactory samples (3-5). Cytopathology, however, requires a high degree of expertise and unfortunately, the access to rapid on-site cytopathology evaluation (ROSE) and the availability of a cytopathologist specifically trained to interpret EUS specimens is not possible in many centers (6). This has created a barrier to the dissemination of EUS in the community and in many countries because the lack of cytology expertise results in a low diagnostic accuracy and therefore in a limited overall perceived utility of EUS (7,8).
- Fine-needle tissue acquisition