The gallbladder is a small pear shaped sac that lies under the liver. Its main function is to store and concentrate bile. Bile is a yellowish green liquid produced by the liver that helps digest fats. Its main function is to break down fats in food.
Bile is passed from the liver through a series of channels, called bile ducts, into the gallbladder, where it is stored. The gallbladder concentrates the bile to increase its effectiveness in digesting fats.
The gallbladder releases bile into the digestive system when it is needed. The gallbladder along with bile ducts is called the biliary system.
Although an important organ, the gallbladder can be safely removed when diseased so that the bile flows directly from the liver into the digestive system. Thus, it is a useful but not essential, organ.
Gallbladder cancer is the cancer of this organ that affects around 670 people each year and affects women more commonly than men. The cancer affects people over 50 more commonly and is rare among younger adults and children.
It is relatively uncommon in Europe but is more common in Chile, Bolivia and Israel. In the United States an estimated 9,810 new cases are diagnosed with 4,480 in men and 5,330 in women.
Most of the gall bladder cancers are of the type adenocarcinoma. These begin in the inner walls and linings of the organ.
Symptoms of gallbladder cancer
The early symptoms of this cancer are often not detectable. As the disease progresses the symptoms manifest themselves and include abdominal pain, nausea, vomiting and jaundice. The urine also becomes a dark yellow or brown colour and stools are pale and chalky. The skin may become itchy. These are symptoms of liver disease as well and need to be evaluated carefully.
Risk factors for gall bladder cancer
Patients with a history of gallstones or in people who have inflammation of the gall bladder (cholecystitis) are at a higher risk of getting gall bladder cancer. However, not all individuals with gallstones will get cancer.
People that are at a greater risk of gallbladder cancer include:
people with non-cancerous benign tumors of the gall bladder called polyps,
those with congenital abnormalities of the bile ducts,
those with a family member (parent, brother or sister) affected with this cancer,
those who are obese or overweight,
those who have a condition called porcelain gall bladder.
Treatment and outlook
Gallbladder cancer is usually detected when operating for gall stones. In some patients it may detected while evaluating for liver disease. Tests for diagnosis include liver function tests and blood tests and imaging studies like ultrasonography, MRI and CT scans.
Gallbladder cancer is treated using a combination of surgical removal of the organ followed by chemotherapy with anticancer drugs and radiation therapy. If detected in fairly early stages, the cancer may be well controlled.
Those with advanced disease however have a poor outlook from treatment and these patients need palliative therapy to ease the symptoms. Palliative care also includes support in very advanced cases and end-of-life care.
Reviewed by April Cashin-Garbutt, BA Hons (Cantab)