Cancer cells have the potential to spread from the extrahepatic bile duct to other parts of the body where they can grow into new tumours. This process is called metastasis. The tumours are also called metastasis (singular) or metastases (plural). Metastases are also called secondary tumours.
Understanding the usual progression of cancer helps the doctor to predict its probable course, plan treatment and anticipate further care.
The most common sites where extrahepatic bile duct cancer spreads are: