Diagnostic Ultrasound - Abdomen and Pelvis

Hepatic Metastases
Diagnoses: Liver
TERMINOLOGY
• Malignant spread of neoplasm to hepatic parenchyma
IMAGING
• Grayscale ultrasound
○ Hypoechoic metastasis: Usually from hypovascular
tumors
○ Hyperechoic metastasis: Hypervascular metastasis
○ "Bull's-eye" or "target" metastatic lesions:Solid mass
with hypoechoic rim or halo
○ Cystic/necrotic metastases: Mural nodules, thick walls,
fluid-fluid levels, internal septa/debris
○ Calcified metastases: Mucinous or ossific primaries
○ Infiltrative/diffuse metastases: Lung or breast primary,
may mimic cirrhosis
• Color Doppler ultrasound
○ Metastatic lesions follow vascularity of primary tumor
○ Contrast-enhanced US increases detectability of hepatic
metastases
KEY FACTS
TOP DIFFERENTIAL DIAGNOSES
• Cysts (vs. hypoechoic or cystic metastases)
• Abscesses (vs. hypoechoic metastases)
• Hemangiomas (vs. hyperechoic metastases)
• Multifocal hepatocellular carcinomas or
cholangiocarcinomas (vs. "target" lesion)
• Steatosis (vs. hypo-/hyperechoic metastasis)
• Hepatic adenomatosis
CLINICAL ISSUES
• Most common malignant tumor of liver
DIAGNOSTIC CHECKLIST
• Rule out other other causes of multiple liver lesions, e.g.,
hepatic cysts, abscesses, or hemangiomas
• Always correlate with clinical history and look for evidence
of primary tumor
(Left) Transverse grayscale
ultrasound in a patient with
breast cancer metastases to
the liver shows that the
metastases have a classic
target appearance ſt in which
rounded lesions are
surrounded by a hypoechoic
rim. (Right) Oblique
transabdominal ultrasound in
a different patient with breast
cancer shows a minimally
hypoechoic, solid metastasis
ſt in the right lobe of the
liver, bulging its contour , as
well as other numerous, more
subtle, hypoechoic solid
masses .
(Left) Transverse ultrasound in
a patient with mucinous colon
cancer metastases to the liver
demonstrates multiple large,
hyperechoic metastases ſt
containing diffuse echogenic
foci related to subtle
calcifications. Note posterior
acoustic shadowing as well
as distortion and compression
of the right portal vein st by
metastases. (Right) Color
Doppler ultrasound of the liver
in the same patient with
mucinous colon cancer shows
multiple hyperechoic
metastases ſt throughout the
liver, some of which abut and
distort the hepatic veins .
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