Lets say someone goes to the doctor: The doctor sees tumors in the lungs and in the liver. Why does the doctor know that its liver cancer that spread to the lungs and not lung cancer that spread to the liver?

Question

Lets say someone goes to the doctor: The doctor sees tumors in the lungs and in the liver. Why does the doctor know that its liver cancer that spread to the lungs and not lung cancer that spread to the liver?

In: 1592

Answer 1

Think of the lung as a giant filter (that’s not its purpose but the capillary beds are so small that’s what it ends up kind of functioning as). The next giant filter is the liver (a primary function of the liver). A LOT of your blood moves through your liver in every complete cycle.

So a primary liver tumor that sheds cells is going to the heart (a part of the body that rarely develops cancer) and then to the lungs which act as a cellular filter. Those cells get embedded and grow.

Most of the time when you think of metastasis the question is what is the next place that the blood is going to go because that is often how the tumor moves.