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Dermographics:
Approximately
5000 cases of carcinoma of the gallbladder are diagnosed in
the United States each year. Native Americans are
disproportionately affected. Among all the countries in the
world, Israel has the highest yearly incidence, with 7.5 cases
per 100,000 men and 13.8 cases per 100,000 women. Mexico,
Bolivia, Chile, and northern Japan also have high rates of
incidence. The cancer is less common in India, Nigeria, and
Singapore.
Carcinoma
of the bile duct is less common than carcinoma of the
gallbladder. About 2500 cases are diagnosed yearly in the U.S.
with an incidence of approximately one case per 100,000 people
per year. The cancer afflicts Native Americans more often,
however, with about 6.5 cases per 100,000 per year. Worldwide,
the incidence is highest in Japan and Israel.
Almost
3 times as many women are affected with carcinoma of the
gallbladder than men. Carcinoma of the bile duct occurs in men
slightly more often than in women. Both cancers are usually
detected when the patient is in the early-to-middle sixties.
Risk
Factors:
No
underlying cause has been identified for carcinoma of the
gallbladder or bile duct. However, several associations have
been observed.
Risk
factors associated with carcinoma of the gallbladder:
-
Gallstones,
found in roughly 75 to 90% of cases of carcinoma of the
gallbladder. Larger gallstones are associated with a
higher chance of developing gallbladder cancer
-
Porcelain
gallbladder, or calcification of the gallbladder as a
result of chronic inflammation (cholecystitis)
-
Inflammatory
bowel disease, manifested as Crohn’s ileocolitis or
ulcerative colitis
-
Typhoid
disease
-
Estrogens
-
Cigarette
smoking
-
Alcohol
consumption
-
Obesity
Several
anatomic abnormalities, including gallbladder polyps,
anomalous connections between the biliary tract and the
intestine, and congential biliary dilatation.
Risk
factors associated with carcinoma of the bile duct:
-
Primary
sclerosing cholangitis, a condition characterized by
extensive scarring of the biliary tract, sometimes
occurring with inflammatory bowel disease
-
Choledochal
cysts, abnormal dilatations of the biliary tract that
usually form during fetal development
-
Hepatolithiasis,
the condition of stone formation within the liver.
-
Liver flukes,
a parasitic infection with certain worms at least
partially responsible for the development of the cancer in
Southeast Asia
-
Thorotrast, a
chemical that was previously injected intravenously during
certain types of X-rays
Other
chemical exposures, especially among workers in the aircraft,
rubber, and wood finishing industries
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