The gallbladder is a small, pear-shaped organ located under the liver. The gallbladder produces bile, a yellow-green fluid that helps the body digest fats. Most changes in the gallbladder, such as cholecystitis or gallstones, are benign. Very rarely, the cells in the gallbladder will grow out of control, developing into cancerous tumours. The most common type of cancer is adenocarcinoma, which grows out of the glandular cells that line the inside of the gallbladder.
Gallstones are the main risk for gallbladder cancer, and this risk is slightly higher in women than in men. Other factors include precancerous changes (such as polyps), smoking, and a family history of gallbladder cancer.
Symptoms are not noticeable in the early stages, and cancer is commonly discovered when the gallbladder is removed during surgery for gallstones. The most common symptoms include persistent abdominal pain, jaundice, bloating or swelling of the abdomen, increase in size of the liver, and buildup of fluid in the abdomen (ascites).
Diagnosis consists of a number of tests, which will distinguish the cancer from other non-cancerous conditions that may be causing similar symptoms. The first diagnostic measures are a health history and a physical exam. Then, blood tests might be ordered to determine gallbladder and liver function. If cancer is present, the tests may find an increased amount of bilirubin (a chemical found in bile), which could indicate blockage of the bile ducts or a problem with the liver due to a gallbladder tumour. The tests can also present an increased amount of alkaline phosphatase, alanine aminotransferase (ALT) and aspartate transaminase (AST), which may all indicate that the cancer has spread to the liver.
Other diagnostic tests include ultrasound, CT scan, tumour marker tests (immunochemistry), biopsy, ERCP (endoscopic retrograde cholangiopancreatography), PTC (percutaneous transhepatic cholangiography), MRI, laparoscopy, and angiography.
Treatment might involve one or more options including surgery, chemotherapy, or radiation therapy. Surgery can consist of several procedures:
- Simple cholecystectomy involves the removal of the gallbladder. Extended cholecystectomy removes, in addition, one inch or more of liver tissue and all of the lymph nodes in the region.
- Radical gallbladder resection involves the removal of the gallbladder, a wedge-shaped section of the liver near the gallbladder, the common bile duct, part or all of the ligaments between the liver and intestines, and the lymph nodes around the pancreas and nearby blood vessels.
- Palliative surgery may sometimes help relieve symptoms caused by gallbladder cancer, even if the tumour cannot be removed completely.
Radiation therapy may be used before surgery to shrink the size of the tumour, or after surgery to destroy any remaining cancer cells. In some cases, intraoperative radiation therapy (IORT) is performed to directly target the organs affected by the cancer and to protect healthy tissues.
Chemotherapy is usually used as a palliative care treatment for gallbladder cancer.