Role of Endoscopic Ultrasonography and Endoscopic Retrograde Cholangiopancreatography in the Diagnosis of Pancreatic Cancer

Abstract

Pancreatic cancer has the poorest prognosis among all cancers, and early diagnosis is essential for improving the prognosis. Along with radiologic modalities, such as computed tomography (CT) and magnetic resonance imaging (MRI), endoscopic modalities play an important role in the diagnosis of pancreatic cancer. This review evaluates the roles of two of those modalities, endoscopic ultrasonography (EUS) and endoscopic retrograde cholangiopancreatography (ERCP), in the diagnosis of pancreatic cancer. EUS can detect pancreatic cancer with higher sensitivity and has excellent sensitivity for the diagnosis of small pancreatic cancer that cannot be detected by other imaging modalities. EUS may be useful for the surveillance of pancreatic cancer in high-risk individuals. Contrast-enhanced EUS and EUS elastography are also useful for differentiating solid pancreatic tumors. In addition, EUS-guided fine needle aspiration shows excellent sensitivity and specificity, even for small pancreatic cancer, and is an essential examination method for the definitive pathological diagnosis and treatment decision strategy. On the other hand, ERCP is invasive and performed less frequently for the purpose of diagnosing pancreatic cancer. However, ERCP is essential in cases that require evaluation of pancreatic duct stricture that may be early pancreatic cancer or those that require differentiation from focal autoimmune pancreatitis.

Keywords: early diagnosis; endoscopic retrograde cholangiopancreatography; endoscopic ultrasonography; pancreatic cancer.

Figure 1

A 68-year-old woman with small pancreatic cancer. (a,b) Computed tomography shows parenchymal atrophy of the pancreatic body (arrow), but no obvious mass. (c) Endoscopic ultrasonography shows a well-defined, irregular hypoechoic mass with a diameter of 8 mm in the pancreatic body (arrow). (d) Surgically resected specimen shows a grayish-white solid mass (arrow). (e) Loupe image of the mass. (f) Moderately differentiated tubular adenocarcinoma (magnification: ×100).

Figure 2

Cases of pancreatic cancer (a–c) and autoimmune pancreatitis (d–f). (a) Computed tomography (CT) shows an irregular and hypovascular 3 cm-seized mass in the pancreatic body (arrow) and dilatation of the upstream main pancreatic duct (MPD). (b) Endoscopic retrograde pancreatography (ERP) shows the MPD stricture in the pancreatic body (arrow) and upstream MPD dilatation. (c) Deviation of side branches from the stricture site is not observed. (d) CT shows a 2 cm-sized mass with hypovascularity in the arterial phase in the pancreatic head (arrow). (e) ERP shows mild strictures of the Wirsung and Santorini ducts (arrow), and slight upstream MPD dilatation. (f) Deviation of side branches from the stricture site is observed.