NCCN Guidelines for Patients™: Colon Cancer
Part 3: Tests of colon cancer
Imaging tests take pictures of the inside of your body. They
can help show if your cancer has spread beyond your
colon. These tests are often easy to undergo. Computed
tomography is the test most used for colon cancer. You
may hear this test called a CT or CAT scan. Other tests
you may have are magnetic resonance imaging (also
called MRI) or positron emission tomography (also called
PET). However, these tests are only suggested in very
specific situations. See Part 7 for more information.
Imaging machines are large and have a tunnel in the
middle. During the test, you will lie on a table that moves
slowly through the tunnel. Imaging tests are done by
technicians, and the results are later read by radiologists.
There are usually no side effects. If radiation is used, the
amount is small.
A CT scan takes many pictures
of a body part from different angles using x-rays (Figure 8).
A contrast dye will be used to make the pictures clearer.
The dye can be injected into your vein or mixed with a
liquid you drink. The dye may cause you to feel flushed
or get hives. Rarely, serious allergic reactions occur.
Tell your doctor and the technicians if you have had bad
reactions in the past. As the machine takes pictures, you
may hear buzzing, clicking, or whirring sounds. A computer
combines the x-rays to make detailed pictures.
Lymph node biopsy
Lymph is a clear fluid that returns fluid and protein to the
blood. It travels between tissues, blood, and lymph nodes in
long, tube-shaped vessels. Lymph vessels and nodes are
naturally found everywhere in the body, which allows colon
cancer to spread far (Figure 9). If your tumor has grown
through the submucosa of the colon wall, your lymph nodes
will be removed during surgical treatment. The nodes will
then be sent to a lab to be tested for cancer cells.
Illustration Copyright © 2011 Nucleus Medical Media, All rights reserved.
Illustration Copyright © 2011
Nucleus Medical Media,
All rights reserved.