Endoscopic Ultrasound in Gastroenteropancreatic Neuroendocrine Tumors

Abstract

Endoscopic ultrasound (EUS) is an advanced endoscopic technique currently used in the staging and diagnosis of many gastrointestinal neoplasms. The proximity of the echoendoscope to the gastrointestinal tract lends itself to a detailed view of the luminal pathology and the pancreas. This unique ability enables endoscopists to use EUS in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs). Diagnostic EUS allows previously unidentified NETs to be localized. EUS also determines tumor management by staging the GEP-NETS, enabling the clinicians to choose the appropriate endoscopic or surgical management. The ability to obtain a tissue diagnosis with EUS guidance enables disease confirmation. Finally, recent developments suggest that EUS may be used to deliver therapeutic agents for the treatment of NETs. This review will highlight the advances in our knowledge of EUS in the clinical management of these tumors.

Surgery management for sporadic small (≤2 cm), non-functioning pancreatic neuroendocrine tumors: A consensus statement by the Chinese Study Group for Neuroendocrine Tumors (CSNET)

“…The seminal article by Rosch et al (19) in 1992 was the first to describe the important role of Endoscopic Ultrasound-Guided Fine-Needle Aspiration (EUS-FNA) in the detection of pNETs. Since then, EUS-FNA has been increasingly used and has become an integral part of the diagnosis of pNETs because of its high sensitivity for detecting, localizing and diagnosing pNETs for >20 years (20).…”

A Perplexing Case of Abdominal Pain That Led to the Diagnosis of Zollinger-Ellison Syndrome

“…Gastrinomas express receptors for somatostatin, allowing SRS scans to be utilized for tumor detection with a higher sensitivity than CT/MRI (reported to be around 80-85%) [13,19]. Recently, EUS has also become an important imaging study and allows for the identification of pancreatic tumors as small as 2-5 mm in diameter, with sensitivity reaching up to 87% [19][20][21]. Our patient underwent extensive imaging with CT, MRI, and EUS before the tumor was finally identified using SRS.…”

Cystic pancreatic neuroendocrine tumors: To date a diagnostic challenge

“…Cytology may also diagnose malignant cystic lesions by demonstrating cells with high grade atypia or neoplastic in the cyst fluid increasing the diagnostic yield of EUS-guided FNA. EUS has an 82% sensitivity and a 92% specificity in identifying PNETs, although EUS is more sensitive in the head of the pancreas than the tail, where predominantly are localized the cystic pancreatic neuroendocrine tumors, thus resulting operator dependent [57,58]. The overall complication rate of EUS-FNAB appears to be 1e2%.…”