Cross-sectional Imaging of Gallbladder Carcinoma: An Update

Abstract

Gallbladder Carcinoma (GBCA) is the most common biliary tract malignancy. As the disease is often diagnosed clinically in an advanced stage, the survival rates are dismal. Imaging studies allow for an early diagnosis of malignancy, though the findings may be indistinguishable from non-malignant disease processes affecting the gallbladder. Attempts have been made to make a specific diagnosis of GBCA at an early stage on imaging studies. Ultrasonography (US) is the most commonly employed technique for gallbladder evaluation. Gallbladder wall thickening is the most common finding of early GBCA and in this context, US is non-specific. Recently, contrast enhanced ultrasound has been shown to be effective in differentiating benign from malignant disease. Multidetector computed tomography represents the most robust imaging technique in evaluation of GBCA. It provides relatively sensitive evaluation of mural thickening, though it is not entirely specific and issues in differentiating GBCA from xanthogranulomatous cholecystitis do arise. Due to its superior soft tissue resolution, Magnetic Resonance Imaging (MRI) provides excellent delineation of gallbladder and biliary tree involvement. When coupled with functional MRI techniques, such as diffusion-weighted and perfusion imaging, it provides a useful problem solving tool for interrogating the malignant potential of nonspecific gallbladder lesions and detection of metastases. Positron emission tomography has a role in detection of distant metastases and following patients following treatment for malignancy. We review the current role of various imaging modalities in evaluating patients with GBCA.

Keywords: CEUS, Contrast Enhanced Ultrasound; GBCA, Gallbladder Carcinoma; HRUS, High Resolution US; MDCT, Multidetector Computed Tomography; MRI, Magnetic Resonance Imaging; PET, Positron Emission Tomography; US, Ultrasonography; carcinoma; gallbladder; imaging.

Figures

Figure 1

Gray-scale US image shows distended GB showing hyperechoic intraluminal contents forming a level suggestive of sludge. If motionless on changing the patient position, this can potentially mimic an endophytic growth. Also seen in the image is a mass arising from the fundus (arrow).

Figure 2

Gray-scale US image shows multiple GB calculi (arrows), GB wall thickening (short arrow) and ill-defined heterogeneous mass arising from the neck of GB (arrow head). CT scores over US in depicting the true extent of adjacent liver invasion.

Figure 3

Gray-scale US image shows multiple GB polyps (arrows) in two patients.

Figure 4

Gray-scale and Doppler US image show GB mass with internal vascularity.

Figure 5

Gray-scale US image shows mild concentric thickening of the GB wall. This appearance is non-specific and is seen in both inflammatory and neoplastic diseases.

Figure 6

CEUS images of the same patient as in Figure 3 show rapid enhancement (upper panel) and washout pattern (lower panel). Histopathological examination of the resected specimen (following laparoscopic cholecystectomy) revealed malignancy.

Figure 7

CEUS of two patients show rapid uptake in the GB wall thickening (arrow). Another patient with GBCA, CEUS demonstrates liver metastases as hypo-enhancing lesions (arrows).

Figure 8

EUS images of GB wall thickening showing resolution of different layers of GB (arrows).

Figure 9

Axial (A) and coronal reformatted (B) images reveal focal asymmetrical thickening of the GB wall (arrows) in the region of body.

Figure 10

Coronal reformatted MIP image shows a large mass replacing GB fossa (arrow). There is marked displacement of the hepatic artery (short arrow) by the mass.

Figure 11

Axial T2 weighted (A) and gadolinium enhanced (B) MR images show soft tissue mass at the neck of the GB (arrows, A and B). Also note bilateral IHBRD (short arrows, A) and cholelithiasis (arrow head, A).

Figure 12

MRCP image in a patient with GBCA shows infiltration and separation of the primary confluence (arrow).

Figure 13

Axial T2 weighted image (A) reveal asymmetrical thickening of the GB wall (arrow, A). Marked dilatation of the CBD (short arrow, A) is due to extrinsic compression by lymph nodes (not shown). Also note subtle hyperintense lesions (arrow heads) and bilateral IHBRD. Diffusion weighted MR (B) shows diffusion restriction (arrow heads) within the focal liver lesions suggestive of metastases.

Figure 14

PET-CT shows an ill-defined hypodense mass replacing the GB fossa (arrow) showing marked FDG avidity. In addition, multiple FDG avid periportal lymph nodes are seen (short arrows).

Figure 15

PET-CT shows asymmetrical mural thickening of the GB (arrow). There is adjacent liver infiltration showing FDG avidity (arrow). A large necrotic FDG avid periportal lymph node is also seen (short arrow).