Gallbladder cancer occurs when malignant cells develop in the gallbladder, a small, pear-shaped organ. Situated in the upper right abdomen just beneath the liver, the gallbladder’s primary role is to store and concentrate bile, a digestive fluid produced by the liver that aids in breaking down fats. The cancer originates in the innermost mucosal layer and can spread outward into surrounding tissues. Because of the gallbladder’s location deep within the body, this cancer can grow undetected. It is an uncommon form of cancer, with fewer than 20,000 cases diagnosed in the United States each year.
Causes and Risk Factors
The precise cause of gallbladder cancer is not fully understood, but certain factors increase the risk. A history of gallstones, which are hardened deposits of digestive fluid, is the most prominent risk factor. While gallstones are common and rarely lead to cancer, the chronic inflammation they can cause is believed to contribute to the cellular changes that initiate the disease.
Other conditions involving long-term inflammation of the gallbladder also elevate the risk. These include chronic cholecystitis (persistent swelling and irritation of the gallbladder), gallbladder polyps (growths on the inner lining), and primary sclerosing cholangitis, a disease that causes inflammation and scarring of the bile ducts.
Demographic factors also play a part. The risk increases with age, with most diagnoses occurring in individuals over 65. The disease is more common in women than in men. Ethnicity is also a risk factor, with higher rates observed in certain populations, as is a family history of the disease.
Symptoms and Diagnosis
Identifying gallbladder cancer is challenging because it often produces no symptoms in its early stages. This lack of warning means the disease is frequently discovered at a more advanced stage. Sometimes, the cancer is found incidentally after the gallbladder is surgically removed for another reason, such as treating gallstones.
When symptoms do appear, they can be similar to those of more common conditions like gallstones. The most common signs are abdominal pain in the upper right belly and jaundice, a yellowing of the skin and eyes that can indicate the cancer is advanced. Other potential symptoms include:
- Unexplained weight loss
- Nausea and vomiting
- Persistent fever
- Bloating
- A lump or mass in the abdomen
The presence of these symptoms prompts an investigation that begins with a physical exam and a review of medical history. Blood tests may be ordered to evaluate liver function. To visualize the gallbladder, physicians use several imaging tests. An ultrasound is often performed first, followed by more detailed CT or MRI scans. A cholangiography, which uses dye to see the bile ducts, may also be used. The definitive diagnosis requires a biopsy, where a tissue sample is examined to confirm the presence of cancer cells.
Gallbladder Cancer Treatment
The treatment approach depends on the cancer’s stage and the patient’s overall health. For cancers confined to the gallbladder, surgery is the primary treatment. The standard procedure is a cholecystectomy (gallbladder removal), and surgeons may also remove part of the adjacent liver and nearby lymph nodes to ensure all cancerous tissue is excised.
For cancers that have spread or cannot be completely removed with surgery, other treatments are employed. Chemotherapy uses drugs to kill cancer cells or slow their growth. It may be given after surgery to eliminate any remaining cancer cells or as the main treatment for advanced-stage cancer.
Radiation therapy uses high-energy rays to destroy cancer cells and can be combined with chemotherapy. Targeted therapy drugs focus on specific abnormalities within cancer cells, causing them to die. Immunotherapy helps the body’s own immune system recognize and fight cancer cells.
Palliative care is part of the overall treatment plan. It focuses on providing relief from the symptoms and stress of the illness to improve the quality of life for the patient and their family. It can be provided alongside curative treatments like surgery or chemotherapy.
Prognosis and Life Expectancy
The prognosis for gallbladder cancer is a statistical estimate of the disease’s likely outcome and cannot predict an individual case. A person’s outcome depends on many factors, including the cancer’s characteristics, the treatments received, and overall health. The prognosis is often poor because the disease is frequently not diagnosed until it has reached an advanced stage.
Survival rates are communicated using the 5-year relative survival rate, which compares people with the same cancer to the general population. For localized cancer that has not spread outside the gallbladder, the 5-year survival rate is approximately 66%. Only about one in five gallbladder cancers are found at this early stage.
When the cancer has spread to nearby structures or lymph nodes (regional stage), the survival rate decreases. For cancer that has metastasized to distant parts of the body, the 5-year survival rate is about 2%. These statistics are based on data from past years and may not reflect outcomes possible with newer treatments.