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Bile duct cancer

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Grades of extrahepatic bile duct cancer

Grading is a way of classifying extrahepatic bile duct cancer cells based on their appearance and behaviour when viewed under a microscope. To find out the grade of a tumour, the biopsy sample is examined under a microscope. A grade is given based on how the cancer cells look and behave compared with normal cells (differentiation). This can give the healthcare team an idea of how quickly the cancer may be growing and how likely it is to spread.

The grade of extrahepatic bile duct cancer is based on the degree of differentiation of cells and their rate of growth.



well differentiated or low grade – slow growing, less likely to spread


moderately well differentiated or moderate grade


poorly differentiated or high grade – tend to grow quickly, more likely to spread

Extrahepatic bile duct cancers are usually slow growing.

Grading plays an important part in planning treatment for extrahepatic bile duct cancer and can also be used to help estimate the prognosis (future outcome).


Dr Roger Zemp Dr Roger Zemp developed an innovative way to track cancer cells.

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The Canadian Cancer Society helps with expenses for children in cancer treatment and their families.

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