EUS는 탐촉자를 위나 십이지장에 위치시킬 수 있어 췌장에서 가장 가까운 곳에서 췌장을 관찰할 수 있으므로 매우 작은 췌장종괴도 인지할 수 있다. 또한 종괴 자체에 대한 감별이 어려울 경우 EUS를 통한 조직 검사는 합병증을 최소화하면서 조직학적 확진율을 높일 수 있다. CE-EUS는 종괴의 특성을 파악하기 어려울 때 도움이 된다. 진단뿐만 아니라 치료에서도 EUS를 활용하고 있는데, 에탄올을 이용한 화학적 소작술 또는 RFA 수술 혹은 경과 관찰이라는 이분법적 치료 방식의 간극을 메워주는 비수술적 치료 방법으로 새롭게 시도되고 있다. PNET의 진단 및 치료에 EUS는 다양하게 활용되고 있으며, 향후 지속적인 발전이 기대된다.

Pancreatic neuroendocrine tumors (PNETs) are rare tumors with malignant potential, but their incidence has appreciably increased over the last few decades. Diagnosis of PNETs is often difficult with conventional imaging methods. Cross-sectional imaging localizes less than 10% of PNETs less than 1 cm in diameter. Endoscopic ultrasound (EUS) has been shown to be superior to other imaging techniques in the preoperative localization and diagnosis of PNETs. The finding of a hyperenhanced lesion on contrastenhanced EUS was highly predictive of PNETs different from adenocarcinoma. Preoperative assessment of tumor differentiation and Ki-67 is an important prognostic factor for grading. Thus, EUS-guided fine needle biopsy may play a key role in the work-up of nonfunctioning PNETs, and attempts to measure Ki-67 on cytologic and histologic samples have been made. According to the European Neuroendocrine Tumor Society guidelines, there is no clear evidence of a survival benefit of surgery for nonfunctioning G1 PNETs <2 cm in diameter. The benefits of curative surgery must be weighed against operative morbidity and mortality. Although surgical resection remains the mainstay for PNETs, EUS-guided ablation offers a relatively safe and effective treatment option in patients deemed unfit for, or who do not want to undergo, surgery. EUS-guided ablation provides an attractive therapeutic nonsurgical option for patients; however, further studies that better elucidate the long-term outcomes with standardization of technique will help define its role in the treatment of PNETs. The role of EUS in the diagnosis and treatment of PNETs is expected to make much progress in the future.

서 론
본 론
    1. EUS의 진단적 역할
    2. EUS의 치료적 활용
결 론
요 약
REFERENCES

• 최준호(단국대학교 의과대학 내과학교실) | Jun-Ho Choi (Department of Internal Medicine, Dankook University College of Medicine) Corresponding author