NCCN Guidelines for Patients
Part 2: Overview of cancer tests
Excisional lymph node biopsy
An excisional lymph node biopsy may be needed if your
doctor finds an enlarged lymph node during the physical
exam or imaging test and an FNA biopsy is not possible
or is inconclusive. This biopsy removes the enlarged
lymph node(s) through a small surgical cut in the skin.
After removing the lymph node(s), your doctor will test
the tissue for cancer cells. Local or general anesthesia
may be used for this surgery.
2.4 Blood tests
Blood tests are not used to find (diagnose) melanoma.
They may be used to monitor melanoma once it has
spread from the skin and lymph nodes to other parts of
the body. Abnormal levels of certain chemicals in the
blood may be a sign that the cancer has spread to distant
parts of the body. An example of the chemical levels that
doctors look for is a high LDH (
level. LDH is a substance found in the blood that is
involved in energy production in cells. If blood test results
are abnormal, your doctor may order other tests.
2.5 Imaging tests
Imaging tests take pictures of the inside of your body.
Typically, these tests are easy to undergo. Imaging
machines are large and have a tunnel in the middle.
During the test, you will lie on a table that will move
slowly through this tunnel as the machine takes many
pictures. Then a computer will combine all pictures into
one detailed picture. Imaging tests can take 15 to 60
minutes to complete.
Often there are no side effects. Imaging tests aren’t used
to find (diagnose) melanoma, but they may be used if you
have signs or symptoms that the melanoma has spread.
Such symptoms include pain that can’t be explained.
Imaging tests may also be given after treatment to check
that treatment worked. The different imaging tests that
may be used for melanoma are described next.
A CT (
omography) scan takes many pictures
of a part of the body from different angles using x-rays.
See Figure 8. A computer combines these x-rays to make
detailed pictures of organs and tissues inside the body.
Before the test, you may be given a contrast dye to make
the pictures clearer. The dye may be put in a glass of
water for you to drink, or it may be injected into your vein.
It may cause you to feel flushed or get hives. Rarely,
serious allergic reactions occur. Tell your doctor if you
have had bad reactions before.
An MRI (
maging) scan is like a CT
scan except it uses radio waves and powerful magnets to
take pictures of the inside of the body. MRI is very useful
for looking at the soft tissues, brain, spinal cord, and
specific areas in the bone. An MRI scan may cause your
body to feel a bit warm. Like a CT scan, a contrast dye
may be used. MRI may be used along with other imaging
tests or if you are concerned about radiation exposure
from other tests.