Cholangiocarcinoma (Bile Duct Cancer)

Introduction

Cholangiocarcinoma is a type of cancer that can occur in the bile ducts. The other name for cholangiocarcinoma is bile duct cancer. It is a very rare type of cancer. There are many medical conditions that can affect the bile duct, but the cancer of the bile duct is the most severe one.

What Is the Bile Duct?

The bile duct is a very thin tube that is known to enter the small intestine from the liver. The important function of the bile duct is to produce a fluid called bile. This bile is required for the digestive process. The structure of the bile duct can be roughly classified into two halves. The upper half of the bile duct is known to be associated with the liver, and the lower half of the bile duct is associated with the pancreas.

What Is Bile Duct Cancer?

Cancer that is known to develop in the bile duct is called, in medical terms cholangiocarcinoma. If cancer occurs in the bile duct, there will be a total dysfunction of the secretions in the bile duct. This type of cancer can occur at any age. Cholangiocarcinoma is classified based on its site of occurrence. They are:

• Distal Cholangiocarcinoma: Distal cholangiocarcinoma occurs in the part of the bile duct that is very near to the small intestine.

• Hilar Cholangiocarcinoma: Hilar cholangiocarcinoma is a type of cancer that surrounds the liver tissues. The other name of hilar cholangiocarcinoma is perihilar cholangiocarcinoma.

• Intrahepatic Cholangiocarcinoma: Intrahepatic cholangiocarcinoma occurs in the portion of the bile duct found within the liver tissues. In some patients, this type of cancer is classified as liver cancer.

What Are the Causes of Cholangiocarcinoma?

Cholangiocarcinoma occurs when the cells in bile ducts undergo genetic changes, causing them to multiply uncontrollably and form a harmful mass (tumor) that can damage healthy tissues.. The precise cause of cholangiocarcinoma is still under medical research. Certain reports have proved that genetic mutations cause cholangiocarcinoma. The parasitic infections are also known to contribute to the occurrence of cholangiocarcinoma.

What Are the Risk Factors for Cholangiocarcinoma?

• Older Age: People who are more than 50 years of age are most commonly affected. The risk is higher in older patients.

• Smoking: The habit of smoking is known to elevate the risk of cholangiocarcinoma.

• Parasitic Infection: The raw or partially cooked food might have infestations of liver parasites, which are known to increase the risk of cholangiocarcinoma. Complications from parasitic infection are predominantly noted in South-East Asia.

• Chronic Liver Disease: Long-term liver diseases, along with scarring, increase the risk of cholangiocarcinoma.

• Primary Sclerosing Cholangitis: The risk rises due to scarring and toughening of the bile duct.

• Ulcerative Colitis: A persistent inflammatory bowel condition that results in inflammation in the colon and rectum, causing symptoms such as abdominal pain and diarrhea

What Are the Symptoms of Cholangiocarcinoma?

The patient might experience general symptoms like:

• Fever.

• Chills.

• Weight loss.

• Loss of appetite.

• Fatigue.

Other serious symptoms experienced by people with cholangiocarcinoma are:

• Jaundice leads to a yellowing of the skin and the white part of the eyes.

• Intensely Itchy Skin: When the bilirubin level increases, there will be an itching sensation in the skin.

• White-Colored and Greasy Stool: The brown color of the stools is due to the bilirubin content. If sufficient bilirubin does not reach the intestine, then white-colored stools are seen.

• Abdominal Pain: Bile duct cancer does not cause any pain in most cases. But, if the tumor is very large, then there are chances for abdominal pain. This pain is aggravated when the tumor is found on the right side.

• Dark-Colored Urine: When the blood is flooded with high bilirubin levels, then the urine might turn yellow.

• Unintended Weight Loss: Patients who are affected by bile duct cancer do not feel hungry resulting in weight loss.

Can Cholangiocarcinoma Cause Jaundice?

When someone has cholangiocarcinoma, their bile ducts get blocked by the cancer, causing bile, a yellowish fluid produced by the liver, to accumulate in the liver or gallbladder. Normally, bile leaves the liver and helps in digestion. The excess bilirubin, a component of bile that gives it its yellow color, enters the bloodstream, resulting in jaundice. This buildup of bilirubin turns the skin and the whites of the eyes yellow. While cholangiocarcinoma is a common cause of jaundice, it's essential to note that jaundice can also occur due to other factors like hepatitis or gallstones blocking the bile duct.

How Is Cholangiocarcinoma Diagnosed?

If the doctor suspects cholangiocarcinoma, will be asked to undergo the following tests.

• Liver Function Test: The effective functioning of the liver will be identified using a liver function test.

• Test for Tumor Marker: The level of antigen for cancer (90-9) will be estimated in the blood. This will serve as a diagnostic tool to identify the overproduction of cancer cells, but it can be used only for provisional diagnosis.

• Endoscopic Retrograde Cholangiopancreatography (ERCP): It is a test for examining the structures of the bile duct using a small camera. Dyes might be necessary for carrying out this procedure.

• Imaging techniques like computed tomography (CT), magnetic resonance imaging (MRI), and magnetic resonance cholangiopancreatography (MRCP) are necessary.

• A biopsy might also be a beneficial procedure.

What Are the Treatment Options for Cholangiocarcinoma?

Treatment is planned according to the stage and extent of cancer. Various imaging procedures are helpful for this purpose. The different treatment options for cholangiocarcinoma are:

• Surgery: The doctors perform the surgery to remove the tumor from the bile duct. If there is additional involvement of other organs, part of them might also be resected.

• Transplantation of the Liver: A healthy donor can help in replacing the unhealthy liver of the patient. This has a lot of health benefits for the patient.

• Biliary Drainage: Biliary drainage is a bypass surgery method to keep the bile duct open and restore the bile flow.

• In addition to this, routine treatment procedures like chemotherapy, radiotherapy, and photodynamic therapy can also be recommended for the patient.

What Are the Recent Advances in the Treatment of Bile Duct Cancer?

On September 2, 2022, the FDA (Food and Drug Administration) approved the use of durvalumab with gemcitabine and cisplatin for adults with biliary tract cancer that cannot be removed by surgery. This approval came after the positive results from the TOPAZ-1 clinical trial. TOPAZ-1 was a clinical trial testing the combination of durvalumab (Imfinzi) with standard chemotherapy for advanced biliary tract cancer. Positive results led to FDA approval for this treatment for patients for whom surgery is not a choice.

How to Prevent Cholangiocarcinoma?

Quit Smoking: consider quitting as smoking is associated with a higher risk of cholangiocarcinoma. If facing challenges in quitting, consulting a healthcare professional for assistance is advisable.

Protect the Liver: Chronic liver disease increases the chances of cholangiocarcinoma. To reduce this risk:

• The individual should consume alcohol in moderation, adhering to the recommended limits of one drink a day for women and up to two drinks a day for men.

• Maintaining a healthy weight is essential to safeguard the liver.

• When handling chemicals, following safety protocols is crucial to prevent liver damage.

Conclusion

Cholangiocarcinoma, a rare and severe bile duct cancer, presents significant challenges. Early detection through tests like liver function assessments and imaging is vital. Treatment options include surgery, transplantation, and innovative approaches like the FDA-approved durvalumab combination. Preventative measures such as quitting smoking, moderate alcohol intake, maintaining a healthy weight, and safe chemical handling are key. Empowering individuals with this knowledge can lead to earlier detection and improved outcomes for those battling this complex condition.