There are various techniques to obtain tissue samples by using fine needle guided by endoscopic ultrasound (EUS). These techniques attempt to obtain the most adequate material with the best quantity and quality for analysis. Currently studies that compare the results concerning capillary technique versus wet technique are not available. In this sense, the authors consider necessary to explore both techniques documenting the results that can define which could be the best method so that it can routinely be used in cases of digestive neoplasia.

The aim of the study will be compare both techniques guided by endoscopic ultrasound (Capillarity versus Wet) and identify which obtains the best sample quality for histopathology analysis as tissue acquisition method in patients diagnosed with tumors of pancreas, biliary tract, liver or lymph nodes.

The researchers are planning a prospective, pilot study in 30 subjects. All patients will be submitted to both techniques of tissue acquisition (capillarity versus wet) in the same procedure of endoscopic ultrasound. Obtained samples for histopathology analysis will be submitted to a blind examination by two different pathologists.

Inclusion Criteria:

• Low or moderate suspicious of malignancy lesion in pancreas, liver or metastatic lymph nodes
• Initial diagnosis according to the characterization by endoscopic ultrasound

Exclusion Criteria:

• Bleeding
• Complications during biopsy procedure
• Needed to use procedures other than those contemplated in the study.
• Patients who not require endoscopic ultrasound evaluation
• Patients who not accept the procedures of the study

Referred to the Endoscopy Department from their corresponding basic health care units within the Mexican Social Security System

This is a pilot study. It means a few patients will be included. We are not subjecting the participants to a higher risk than the endoscopic ultrasound itself and the procedures performed here are usual. The authors will only document the experience.