Malignant Neoplasms of the Gallbladder

Gallbladder Carcinoma

Gallbladder carcinoma is the fifth most common malignancy of the gastrointestinal tract [37]. While there doesn't appear to be any difference between males and females in the incidence of gallbladder carcinoma, there are indications of demographic differences in the age of patients diagnosed with this neoplasm: in the United States the average age at diagnosis is about 70 years, while in India it is 40-50 years.

The four most important factors associated with the development of gallbladder carcinoma are genetic anomaly, gallstones, congenital abnormal choledocho-pancreatic junction, and porcelain gallbladder. With regards to genetic factors, a mutation of the k-ras gene, overexpression of the c-erbB-2 gene and decreased expression of the nm23 gene have been observed in patients with gallbladder carcinoma [13,18]. An association between gallbladder carcinoma and gallstones is well known, and this causal relationship is the reason for performing cholecystectomy for cholelithiasis as a preventive measure for gallbladder carcinoma. Gallbladder carcinoma is associated with an abnormal choledocho-pancreatic junction because in this condition pancreatic juice can reflux into the common bile duct. The mixture of pancreatic juice and bile leads to chronic inflammation of the gallbladder with subsequent metaplasia, dysplasia, and carcinoma [30]. Finally, porcelain gallbladder, which is a diffuse calcification of the gallbladder wall, is also a predisposing factor: an estimated 22% of patients with porcelain gallbladder develop carcinoma [7, 55].

Approximately 60% of all neoplasms originate in the fundus of the gallbladder, while 30% originate in the body and 10% in the neck. Nearly 85% of primary carcinomas of the gallbladder are ade-nocarcinomas; the remainder are anaplastic or squamous cell carcinomas. The adenocarcinomas can be subdivided into various subtypes, including well-differentiated, papillary, intestinal, pleo-morphic giant cell, poorly-differentiated small cell, and clear cell types.

Histologically, gallbladder carcinomas have three major patterns of presentation:

1) focal or diffuse thickening of the gallbladder wall;

2) polypoid mass originating in the gallbladder wall and projecting into the lumen;

3) mass obscuring or replacing the gallbladder, often invading adjacent liver, with or without multiple satellite nodules [59, 60].

Fig. 34. Gallbladder adenoma. US reveals a small, well-defined, hyperechoic, sessile lesion (arrow)

Fig. 35. Gallbladder carcinoma. US reveals an heterogeneous, hypo- and hyperechoic mass (white arrows) that replaces the gallbladder. A coarse stone with acoustic shadow can be seen within the mass (arrowhead)

Lymph node involvement is also a common finding in gallbladder carcinoma. Most patients with carcinoma of the gallbladder present with either acute cholecystitis or symptoms of malignancy, including constant right upper abdominal quadrant pain, malaise, weight loss, and jaundice. Patients sometimes have a long history of episodic cholecystitis. Gallbladder carcinoma is occasionally an incidental finding on abdominal imaging studies [40].

On US, gallbladder carcinomas may cause mild to marked mural thickening in a focal or diffuse pattern with irregular and mixed echogenicity.

Carcinomas confined to the gallbladder mucosa may present as flat or slightly raised lesions with mucosal irregularities that are difficult to appreciate sonographically. On the other hand, polypoid carcinomas may be hyperechoic, hypoechoic, or isoechoic relative to the liver. These lesions are fixed to the gallbladder wall, and do not cause an acoustic shadow. Gallstones are usually present, in which case a large mass obscuring or replacing the gallbladder is a common presentation (Fig. 35). The echotexture of this manifestation is often complex with regions of necrosis and small amounts of pericholecystic fluid often present [60, 69]. Color Doppler US usually shows a hypovascu-lar mass. However, a color signal may be seen at the periphery due to the hypervascularity of the peripheral components [69].

CT is inferior to US for evaluating the gallbladder wall for mucosal thickening or irregularity. Focal malignant wall thickening and polypoid cancer are both usually hyperdense on CT images acquired after the administration of intravenous contrast material. However, infiltrating carcinoma that replaces the gallbladder often shows irregular contrast enhancement with scattered regions of internal necrosis (Fig. 36) [60]. Invasion of the liver, satellite lesions, and bile duct dilatation are common findings in this form of gallbladder carcinoma [69].

The MR findings for gallbladder carcinoma are similar to those reported for CT. The tumor usual-

Normal And Sick Gallbladder

Fig. 36a-d. Gallbladder carcinoma on CT. Unenhanced CT (a) reveals an ill-defined slightly hypodense mass (white arrows) surrounding a coarse irregular, and heterogeneous stone (white arrowhead). In the arterial phase after contrast material administration (b) the neoplasm remains poorly-delineated and poorly-enhanced. In the portal-venous phase (c) the lesion appears heterogeneously isodense, but better defined against the normal liver. In the equilibrium phase (d) the neoplasm is more homogeneous and a thin hyperdense peripheral rim can be seen

Fig. 36a-d. Gallbladder carcinoma on CT. Unenhanced CT (a) reveals an ill-defined slightly hypodense mass (white arrows) surrounding a coarse irregular, and heterogeneous stone (white arrowhead). In the arterial phase after contrast material administration (b) the neoplasm remains poorly-delineated and poorly-enhanced. In the portal-venous phase (c) the lesion appears heterogeneously isodense, but better defined against the normal liver. In the equilibrium phase (d) the neoplasm is more homogeneous and a thin hyperdense peripheral rim can be seen

Tumor Gallbladder Mri

Fig. 37a-g. Gallbladder carcinoma on MR. On T2-weighted images (a) a gallbladder stone (arrow) together with some solid material in the gallbladder can be seen infiltrating the surrounding liver tissue of the right liver lobe. On the corresponding T1-weighted image the infiltrating tissue appears hypointense (b). On Tl-weighted fat-suppressed images (c) some hyperintense areas indicative of hemorrhage can be noted inside the solid components. Arterial phase Tl-weighted images acquired after the bolus administration of Gd-BOPTA reveal irregular enhancement of the periphery of the infiltrated right liver lobe (d). Enhancement (arrow/) of papillary solid areas in the gallbladder can also be detected on portal-venous phase images (e). This is even more obvious on Tl-weighted fat-suppressed images in the equilibrium phase (f) in which tumor growth in the gallbladder is clearly visualized (arrow). Additionally, homogeneous enhancement of the infiltration of the right liver lobe due to desmoplastic reaction can be noted, which is typical for cholangiocellular carcinoma. In the hepatobiliary phase (g), the infiltrated areas of the right liver lobe are once again hypointense, evidencing the malignant nature of the lesion. Note the excretion of the contrast agent in the bile duct (arrow) and the enhancement of the surrounding liver tissue compared with the unenhanced T1-weighted image.

ly has increased signal intensity relative to the liver on T2-weighted images and poorly-delineated contours. These lesions are either isointense or hypointense relative to the liver on Tl-weighted images. The tumor generally shows poor and heterogeneous enhancement on dynamic phase imaging and often appears hyperintense on fat-suppressed Tl-weighted images in the equilibrium phase [57]. On delayed hepatobiliary phase images after the administration of Gd-BOPTA, the tumor appears as a heterogeneous hypointense mass (Fig. 37). A significant signal drop is usually not seen after

SPIO administration and the lesion is usually hyperintense compared to the normal liver parenchyma [57].

Gallbladder Carcinoid

Gallbladder carcinoid is a rare tumor that represents less than 1% of all digestive tract carcinoids. Patients are usually young or middle-aged adults and there is no clear sex predominance. Associa tions of gallbladder carcinoid with Zollinger-Ellison syndrome, multiple endocrine neoplasia, and carcinoid syndrome have previously been shown.

Macroscopically, these tumors appear as grey to yellow intramural nodules measuring from a few millimetres to 3-4 cm. The neoplastic cells are composed of uniform, small cells with eosinophilic granular cytoplasm. Most carcinoids are argy-rophilic.

Small carcinoids of less than 1 cm are usually incidental findings in cholecystectomy specimens [49]. On imaging, gallbladder carcinoids manifest as polypoid masses that sometimes obstruct the cystic duct.

Get Rid of Gallstones Naturally

Get Rid of Gallstones Naturally

One of the main home remedies that you need to follow to prevent gallstones is a healthy lifestyle. You need to maintain a healthy body weight to prevent gallstones. The following are the best home remedies that will help you to treat and prevent gallstones.

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