Endoscopic ultrasound-guided tissue acquisition for splenic lesions: A systematic review and meta-analysis of diagnostic test accuracy

Current perspectives on the diversification of endoscopic ultrasound-guided fine-needle aspiration and biopsy

Endoscopic ultrasound-guided tissue acquisition (EUS-TA) has undergone significant advancements since it was first reported in 1992. Initially focused on the pancreas, EUS-guided fine-needle aspiration (FNA) has now been extended to encompass all organs proximal to the gastrointestinal system. Recently, a novel fine-needle biopsy (FNB) needle with an end-cut tip was developed, allowing for the collection of specimens suitable for histological assessment, a feat hard to achieve with traditional needles. The FNB needle holds promise for applications in immunohistochemistry staining and genetics evaluation, and it has the potential to yield specimens of comparable quality to core needle biopsy during percutaneous puncture, especially for lesions beyond the pancreas, such as lymph nodes. This review focuses on the efficacy of EUS-FNA/FNB for extended target regions, specifically lymph nodes, spleen, adrenal gland, and ascites. The indications for EUS-FNA have greatly expanded beyond the pancreas over the years, and future improvements and innovations in puncture needles will allow for the collection of higher-quality specimens, which is expected to play a significant part in personalized cancer treatment.

Endoscopic ultrasound-guided tissue acquisition beyond the pancreas

Endoscopic ultrasound (EUS) offers the ability to obtain tissue material via a fine needle under direct visualization for cytological or pathological examination. Prior studies have looked at EUS tissue acquisition; however, most reports have been centered around lesions of the pancreas. This paper aims to review the literature on EUS tissue acquisition in other organs (beyond the pancreas) such as the liver, biliary tree, lymph nodes, and upper and lower gastrointestinal tracts. Furthermore, techniques for obtaining tissue samples under EUS guidance continue to evolve. Specifically, some of the techniques that endoscopists employ are suction techniques (i.e., dry heparin, dry suction technique, wet suction technique), the slow pull technique, and the fanning technique. Apart from acquisition techniques, the type and size of the needle utilized play a major role in the quality of samples. This review describes the indications for tissue acquisition for each organ, and also describes and compares the various tissue acquisition techniques, as well as the different needles used according to their shape and size.