What is gallbladder cancer?
Gallbladder cancer is a cancer that starts in the gallbladder. To understand this cancer, it helps to know about the gallbladder and what it does.
About the gallbladder
The gallbladder is a small, pear-shaped organ under the liver. Both the liver and the gallbladder are behind the right lower ribs. In adults, the gallbladder is usually about 3 to 4 inches long and normally no wider than an inch.
The gallbladder concentrates and stores bile, a fluid made in the liver. Bile helps digest the fats in foods as they pass through the small intestine. Bile is either released from the liver directly into ducts that carry it to the small intestine, or is stored in the gallbladder and released later. When food (especially fatty food) is being digested, the gallbladder contracts and releases bile through a small tube called the cystic duct. The cystic duct joins up with the common hepatic duct, which comes from the liver, to form the common bile duct. The common bile duct joins with the main duct from the pancreas (the pancreatic duct) to empty into the duodenum (the first part of the small intestine) at the ampulla of Vater.
The gallbladder is helpful, but you do not need it to live. Many people have their gallbladders removed and go on to live normal lives.
Types of gallbladder cancers
About 9 out of 10 gallbladder cancers are adenocarcinomas. An adenocarcinoma is a cancer that starts in cells with gland-like properties that line many internal and external surfaces of the body (including the inside the digestive system).
Papillary adenocarcinoma or just papillary cancer is a type of gallbladder adenocarcinoma that deserves special mention. When seen under a microscope, the cells in these gallbladder cancers are arranged in finger-like projections. In general, papillary cancers are not as likely to grow into the liver or nearby lymph nodes. They tend to have a better prognosis (outlook) than most other kinds of gallbladder adenocarcinomas. About 6% of all gallbladder cancers are papillary adenocarcinomas.
Other types of cancer, such as adenosquamous carcinomas, squamous cell carcinomas, small cell carcinomas, and sarcomas, can develop in the gallbladder, but these are uncommon.
What are the key statistics about gallbladder cancer?
The American Cancer Society’s estimates for cancer of the gallbladder and nearby large bile ducts in the United States for 2015 are:
- About 10,910 new cases diagnosed: 4,990 in men and 5,920 in women
- About 3,700 deaths from these cancers: 1,660 in men and 2,040 in women
Of these new cases, a little less than 4 in 10 (about 4,000 cases) will be gallbladder cancers.
Gallbladder cancer is not usually found until it has become advanced and causes symptoms. Only about 1 of 5 gallbladder cancers is found in the early stages, when the cancer has not yet spread beyond the gallbladder.
The chances of survival for patients with gallbladder cancer depend to a large extent on how advanced it is when it is found.