 Rationale: Rapid on-Site Evaluation ROSE of cytologic specimens acquired with EUS-guided fine needle aspiration EUS-FNA represents the most accurate available technique to reach a definitive diagnosis in patients with pancreatic solid masses. Cytologic interpretation, however, requires a high degree of expertise rarely found outside high volume centers and ROSE is not available in many countries. This has created a barrier to the widespread dissemination of EUS in the community and throughout the world, because the lack of cytologic expertise has resulted in a low diagnostic accuracy and, therefore, in a limited perceived utility of EUS. A device that is able to: i acquire histologic core biopsy samples usually easier to be interpreted; ii be used by most of the endosonographers and not only by the experts; iii have a performance at least not inferior to ROSE, will represent a major breakthrough in the field of EUS tissue acquisition. The availability of such needles will determine a shift from cytology to histology that will overcome some of the limitations of cytology and ROSE, thus strongly contributing to the diffusion of EUS throughout the world and in the community. 