Overview

Endoscopic ultrasound (EUS) is a widely recognized tool for over 30 years for diagnosing intra-abdominal lesions and gastrointestinal cancers, especially pancreatic neoplasia. In most hospitals, it is the preferred method for sampling using fine-needle aspiration (EUS-FNA) or histology needle aspiration biopsy (EUS-FNB) to obtain cytological and histological material for an anatomopathological diagnosis. It is also recognized by current oncology guidelines.

Numerous factors can affect the efficacy of this technique, such as the needle size, type (cytology or histology), number of passes made on the lesion, the presence or absence of a pathologist in the endoscopy room, the experience of the endoscopist, etc.

Currently, EUS-FNA or EUS-FNB are recommended interchangeably for diagnosis; however, it appears that histology needles (EUS-FNB) allow for greater diagnostic efficacy by obtaining a cellular block with fewer passes, which allows for more advanced anatomopathological analysis (such as immunohistochemistry or molecular analysis).

Regarding the technique for performing the puncture and acquiring the sample, current European guidelines recommend sampling using EUS-FNA or FNB by dry suction with a 10 mL syringe. However, other recognized techniques, such as using a stylet with the "slow-pull" technique (not positioning for or against) or liquid biopsy (which could obtain larger cellular blocks compared to dry puncture), are widely used and could obtain better samples, but there is no clear consensus currently.

Investigators' goal is to conduct a randomized clinical trial of three EUS-FNB techniques (dry puncture vs slow-pull vs wet puncture) used in daily clinical practice to evaluate which of the three techniques has greater efficacy in cytological and pathological diagnosis.

Eligibility

Inclusion criteria

• Age ≥ 18 years
• Patients referred for EUS-FNB after imaging tests (CT, MRI, or abdominal ultrasound) of pancreatic, non-pancreatic intraabdominal, mediastinal, or pelvic lesions greater than 1 cm.
• Signed informed consent.

Exclusion criteria

• Coagulopathy (INR> 1.5) or thrombocytopenia (<50,000)
• Severe heart or respiratory failure that contraindicates sedation.
• Use of anticoagulants and antiplatelet agents that cannot be suspended.
• Use of a needle of a different gauge to 22G
• Refusal to sign informed consent.