Prospective Randomized Study Comparing the 25-gauge Franseen Needle and the 25-gauge Standard Needle for EUS-guided Fine-needle Sampling of Solid Pancreatic Lesions Without Rapid on Site Evaluation

This is a randomized trial conducted at a unique center. The aim of this study is to compare the diagnostic yield (primary outcome) of EUS-guided sampling of pancreatic solid lesions obtained with the 25-gauge Franseen and the 25-gauge standard needle in patients undergoing EUS-guided sampling of pancreatic solid masses without ROSE. Secondary outcomes are the number of extra passes with each needle required to reach adequate core, possibility to perform immunohistochemistry and the adverse event rate.

Patients with a suspected solid pancreatic lesion larger than 15 mm, identified by CT or MRI and referred to EUS-guided sampling will be eligible for inclusion. Patients will be excluded in case of cystic lesion, or the lesion was not detected in EUS, or if the coagulation parameters are abnormal (INR> 2, platelet count < 50,000). The pancreatic mass will be puncture, for expert endoscopist, firstly with a needle according to randomization, followed by another one. Will be make a touch print with the specimen obtained with the needles and, subsequently, all the specimen will be put in formaldehyde solution for cell-block analysis.

Diagnostic yield of cell block will be defined as enough histologic tissue core containing pancreatic parenchyma or tumor with dysplastic cells enough for the correct tissue diagnosis. In the presence of malignant tissue in core specimens, it will be calculated the proportion of the area positive for malignancy compared to the total area of the core and then the each needle yield will be defined.