Clinical Impact of Endoscopic Ultrasound-Guided Fine-Needle Biopsy in Radiologically Suspected Pancreatic Neuroendocrine Tumors.

Objectives

Incidental diagnosis of pancreatic neuroendocrine tumors (PNETs) is increasing. Its surgical indication depends on the risk of progression, whereas histological features can be assessed by endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB). However, its systematic use remains a matter of debate. We aimed to analyze the impact of EUS-FNB on therapeutic management in patients with radiologically suspected PNETs.

Methods

In this retrospective observational single-center study, all patients with suspected PNET by radiological imaging who underwent EUS-FNB from 2011 to 2023 were enrolled. Patients with multiple endocrine neoplasia or previous/metastatic tumors were excluded. The North American Neuroendocrine Tumor Society (NANETS) consensus was followed, and modifications in management due to FNB findings were detailed.

Results

Of 212 patients undergoing EUS-FNB for suspected PNETs, 146 patients were included. No severe adverse events were reported during the biopsy procedure. Surgical pathology showed that the median tumor size was 17 mm, 32.2% were located in the pancreatic head. Therapeutic management was modified in 12 (8.2%) patients based on EUS-FNB findings due to different tumor types or additional high-risk tumor feature (n = 5), different tumor grading (n = 4), and absence of malignancy (n = 3).

Conclusion

Systematic EUS-FNB improves accuracy in PNET diagnosis and is associated with a non-negligible rate of change in management. Large-scale studies are needed to confirm our findings.