Table of Contents Table of Contents
Previous Page  12 / 112 Next Page
Show Menu
Previous Page 12 / 112 Next Page
Page Background


NCCN Guidelines for Patients


Adolescents and Young Adults with Cancer, Version 1.2017

Cancer on the move

Normal cells typically stay where they are in the body.

But cancer cells can escape from where they started

and move to other parts of the body—a process

called metastasis.

The ability to spread is what makes cancer so

dangerous. Once cancer cells get loose, they can

travel to distant parts of the body through the blood

or lymphatic system. The lymphatic system is made

up of lymph, lymph nodes, and lymph vessels. When

cancer cells settle into new places in the body they

can replace or damage healthy cells. In time, cancer

cells can damage other tissues or organs.


Cancer that has spread to a nearby body part

is called a

local metastasis.


Cancer that has spread to a body part far from

the original area it started is called a



The cells that spread to other areas of the body are

still called by the name of the original place it started.

The original place the cancer started in the body is

also referred to as the primary tumor. For example,

when breast cancer cells spread to the lung it is not

called lung cancer; instead it is called metastatic

breast cancer.

Causes of cancer

Doctors are not completely sure what causes cancer.

Many things can cause cancer or put someone at

risk for the disease. Doctors do know that cancer

gets its start when something goes wrong with the

genes—a process called mutation. Mutations can be

passed on from a parent and present before you are

born (inherited) or caused by later genetic damage


Inherited mutations are found in all of the body’s cells.

People with inherited genetic mutations have a higher

risk for certain cancers, but that doesn’t mean they

will definitely develop cancer. Only a small number of

cancers have an inherited mutation.

Acquired mutations, on the other hand, are found in

every person with cancer. Unlike inherited mutations,

which affect every cell in the body, acquired mutations

happen in specific cells or types of cells.


But I'm too young to have cancer!

What is cancer?