Endosonography in solid and cystic pancreatic tumors

Abstract

Pancreatic tumors being either benign or malignant can be solid or cystic. Although diverse in presentation, their imaging features share commonalities and it is often difficult to distinguish these tumors. Endoscopic ultrasonography (EUS) is the most sensitive of the imaging procedures currently available for characterizing pancreatic tumors, and is especially good in identifying the smaller sized tumors. Additional applications inclusive of EUS-guided fine needle aspiration (EUS-FNA) are useful in tissue sampling and preoperative staging of pancreatic tumors.Although diagnostic capabilities have greatly evolved with advances in EUS and tissue processing technology (cytology, tumor markers, DNA analysis), differentiation of benign and malignant neoplasms, neoplastic and non-neoplastic (chronic pancreatitis) conditions, continues to be challenging.Recent innovative applications include contrast-enhanced EUS with Doppler mode, contrast-enhanced harmonic EUS, 3-dimensinal EUS, and EUS elastography. Incorporation of these methods has improved the differential diagnosis of pancreatic tumors. Finally, a multi-disciplinary approach involving radiology, gastroenterology and surgical specialties is often necessary for accurate diagnosis and management of solid and cystic pancreatic tumors.

Figure 1

Endosonography of pancreatic adenocarcinoma. A: A 4.0 × 3.4 cm hypoechoic, heterogeneous mass with ill-defined borders and cystic space in the head of the pancreas; B: A 4.0×3.8 cm hypoechoic mass in the uncinate region. Fine needle aspiration confirmed diagnosis.

Figure 2

Endosonography of chronic pancreatitis in the head (A), body (B) and tail (C) of the pancreas in the same patient. Chronic pancreatitis can present as a mass simulating pancreatic cancer. Conversely, calcification and lobulation in chronic pancreatitis can conceal a malignant lesion.

Figure 3

Endosonography of pancreatic neuroendocrine tumors in head (A), body (B) and tail (C) of the pancreas in the same patient. All lesions are hypoechoic well demarcated homogenous masses. Fine needle aspiration confirmed diagnosis.

Figure 4

Endosonographic images of different mucinous cysts in the pancreas. A: Multiloculated, septated cyst in pancreatic head; B: A cyst in the tail of the pancreas with a thick wall; C: A cyst in tail of the pancreas with an intramural nodule (arrow).

Figure 5

Endosonography of intraductal papillary mucinous neoplasm of the pancreas in the same patient. A: Dilated main pancreatic duct (∼11.5 mm) in the head; B: uncinate process of the pancreas; C: Intraductal growth (∼9 mm, arrow) within the dilated main pancreatic duct (arrow).

Figure 6

Endosonography of solid-pseudo papillary tumor of the pancreas. A: An approximate 2×2 cm anechoic cyst in the tail of the pancreas with hypoechoic solid component; B: After fine needle aspiration of approximately 3 cc of clear viscous fluid, the solid component of the lesion was also sampled within the same pass.

Figure 7

Endosonographic images of three round, hypoechoic lesions in the head (A), body (B) and tail (C) in the same patient. Fine needle aspiration was consistent with metastatic carcinoma from a primary lung cancer.