Table 1.

Main imaging findings of PDAC on ultrasound, CT, and MRI.

Imaging Technique	Imaging Findings
Ultrasound	‑Tumor in pancreatic head: hypoechoic mass + double duct sign (dilatation of the pancreatic duct and dilatation of the bile duct) ‑Tumor in body/tail: very difficult to be detected; if visible hypoechoic mass with upstream dilatation of the pancreatic duct ‑Poor vascularity on Doppler-US
Computed Tomography	‑Ill-defined hypoattenuating mass, abrupt ductal cut off at the site of the mass double duct sign, poor enhancement on pancreatic and venous phases compared to normal pancreatic parenchyma, tendency to isoattenuation to normal pancreatic parenchyma in delayed phases ‑Isoattenuating mass in 5.4–11% of cases, mainly in case of small lesions, abrupt ductal cut off at the site of the mass
Magnetic Resonance Imaging	‑Hypointense compared to normal pancreatic parenchyma on T1-weighted precontrast images, variable intensity on T2-weighted images, slower enhancement than the normal pancreas thus being hypovascular compared to normal pancreatic parenchyma on pancreatic and portal venous phases, and isovascular to normal pancreatic parenchyma in delayed phases, usually restricted diffusion on diffusion weighted images, abrupt ductal cut off at the site of the mass, double duct sign