Gallbladder cancer

Gallbladder cancer is a relatively uncommon malignancy that primarily affects older adults, particularly those over the age of 65.

It is especially prevalent in regions such as central and South America, central and eastern Europe, Japan, and northern India, as well as among certain ethnic groups like Native American Indians and Hispanics.

Early diagnosis is rare, and the prognosis is generally poor, with a five-year survival rate of about 19% in the USA.

Signs and Symptoms

The early symptoms of gallbladder cancer often mimic those of gallbladder inflammation due to gallstones, making early diagnosis challenging. Common symptoms include steady pain in the upper right abdomen, indigestion, bilious vomiting, weakness, loss of appetite, weight loss, and jaundice. Later in the disease course, symptoms may include biliary and stomach obstruction.

Courvoisier's law, which states that a palpably enlarged, nontender gallbladder accompanied by mild painless jaundice is unlikely due to gallstones, can be a useful diagnostic clue suggesting possible malignancy.

Risk Factors

Gallbladder cancer is approximately twice as common in women as in men and typically occurs in the seventh and eighth decades of life. Other risk factors include obesity, chronic cholecystitis and cholelithiasis, primary sclerosing cholangitis, chronic Salmonella typhi infection, gallbladder polyps, and congenital abnormalities of the bile duct such as choledochal cysts. Porcelain gallbladder, a condition where the gallbladder wall becomes calcified, has also been associated with an increased risk of gallbladder cancer.

Diagnosis

Early diagnosis of gallbladder cancer is often not possible. High-risk individuals, such as women or Native Americans with gallstones, are closely monitored. Diagnostic tools include transabdominal ultrasound, CT scan, endoscopic ultrasound, MRI, and MR cholangiopancreatography (MRCP). Many cases of gallbladder cancer are discovered incidentally during evaluations for cholelithiasis. A biopsy is essential to confirm the malignancy of a tumorous growth.

Treatment

Treatment options for gallbladder cancer depend on the stage at which it is diagnosed. If detected early, surgical intervention, known as radical or extended cholecystectomy, can be effective. This surgery involves the removal of the gallbladder along with a portion of the liver and the nearby lymph nodes. In some cases, a hepatectomy or removal of the bile duct may be necessary. However, due to the generally poor prognosis, many patients do not survive beyond a year post-surgery.

For cases where surgery is not feasible, other treatment options include endoscopic stenting or percutaneous transhepatic biliary drainage (PTBD) to alleviate jaundice, and stenting of the stomach to relieve vomiting. Chemotherapy and radiation therapy may also be employed, sometimes in conjunction with surgery.

Epidemiology

Gallbladder cancer is relatively rare, with fewer than 5,000 cases diagnosed annually in the United States. It is more common in South America, Japan, and Israel. In Chile, it is the fourth most common cause of cancer deaths. The incidence of gallbladder cancer is higher in women, and the age-adjusted incidence rates are highest in Chile and the state of Assam in India. Most tumours are adenocarcinomas, with a small percentage being squamous cell carcinomas.

Research

Advancements in genomic profiling are helping to unravel the biology of biliary tract cancers, including gallbladder cancer. Research into the genomic characteristics of these cancers is providing insight into deficiencies in the tumour cells' DNA repair mechanisms. Approximately 25% of patients with biliary tract cancer exhibit some form of DNA damage repair deficiency, which could potentially be exploited to improve responses to treatments such as chemotherapy, radiotherapy, or immunotherapy.

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Self-assessment MCQs (single best answer)

Which of the following regions is NOT listed as having a high prevalence of gallbladder cancer?

What is the five-year survival rate for gallbladder cancer in the USA?

Courvoisier's law suggests that a palpably enlarged, nontender gallbladder accompanied by mild painless jaundice is unlikely due to:

Which of the following is NOT a risk factor for gallbladder cancer?

Which diagnostic tool is essential to confirm the malignancy of a tumorous growth in the gallbladder?

Which treatment option is typically employed for early-stage gallbladder cancer?

In which country is gallbladder cancer the fourth most common cause of cancer deaths?

What percentage of biliary tract cancer patients exhibit some form of DNA damage repair deficiency?

Which imaging technique is NOT typically used in the diagnosis of gallbladder cancer?

What type of carcinoma is most commonly associated with gallbladder cancer?