Diagnostic Ultrasound - Abdomen and Pelvis

Gallbladder Carcinoma
Diagnoses: Biliary System
TERMINOLOGY
• Most common malignancy of biliary tree, with worst
prognosis
• Epithelial neoplasm arising from gallbladder (GB) mucosa
with predilection for women and the elderly
• Characterized by early locoregional spread directly to liver
and peritoneum and porta hepatic and paraaortic lymph
nodes (LNs)
IMAGING
• 3 main morphological types
○ Large soft tissue mass infiltrating gallbladder
fossa/replacing GB, ± invading liver (most common)
○ Diffuse or focal GB wall thickening: Asymmetric,
irregular, extensive thickening
○ Polypoid intraluminal mass: > 1 cm, thickened base,
irregular margins
• US for initial detection and characterization, CECT or MR for
preoperative assessment and staging
KEY FACTS
TOP DIFFERENTIAL DIAGNOSES
• GB Polyp
○ Typically < 1 cm ± multiple = benign cholesterol polyp
• Focal or diffuse wall thickening
○ Hyperplastic cholecystoses
– Tiny intramural echogenic foci with "comet tail"
artifact
○ Chronic cholecystitis
– Contracted GB (lumen may be obliterated)
○ Xanthogranulomatous cholecystitis
– Infiltrative intramural inflammatory process resulting
in ill-defined GB wall thickening
– Nearly impossible to differentiate from gallbladder
carcinoma preoperatively
CLINICAL ISSUES
• Most are adenocarcinoma, mean 5-year survival rate 5-10%
• Preoperative diagnosis occurs in < 20% of patients
(Left) Graphic shows pathways
of local tumor invasion from
carcinoma of gallbladder st:
Direct tumor infiltration to
liver parenchyma ſt;
retrograde spread along
biliary tree . (Right)
Longitudinal US in a 67-yearold
man shows a broad-based
ſt, hypoechoic polypoid mass
protruding into the
gallbladder (GB) lumen. (Used
with permission from the
American Institute for
Radiologic Pathology archives,
Case ID #4067.)
(Left) GBC can also appear as
irregular, asymmetric,
lobulated fundal wall
thickening ſt with mucosal
disruption , as in this 48-
year-old woman. (Used with
permission from the AIRP
archives, Case ID # 422.)
(Right) Most commonly, GBC
appears as heterogeneous
lobulated echogenic
distension of the GB ſt,
usually in presence of
shadowing stones. Marginal
obliteration and direct hepatic
invasion are ominous signs.
(Used with permission from
the AIRP archives, Case ID #
923.)
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