NCCN Guidelines for Patients™: Multiple Myeloma
2.4 Tissue tests
To confirm the presence of cancer, a sample of tissue or
fluid is removed from the body. This is called a biopsy. A
biopsy is generally a safe test and can typically be done
in under 30 minutes. After the samples are collected,
they are sent to a lab for testing. A pathologist will look
at the samples with a microscope for myeloma cells and
may do other tests. It usually takes several days before
the results are known. The three types of biopsies used
for myeloma are:
Bone marrow aspiration and biopsy
An aspiration is a biopsy that removes a sample of fluid
called an aspirate. The bone marrow aspirate is removed
with a needle and syringe. In contrast, a bone marrow
biopsy uses a thicker, hollow needle to remove a sample
of bone with solid marrow. Usually both tests are done at
the same time on the hip bone.
These biopsies are done as outpatient tests. First, you
may be given a sedative injected with a needle into your
vein. Next, you will receive a local anesthetic, which
means your skin will be cleaned then your skin and bone
beneath will be numbed with medication. After the area
is numbed, a needle will be inserted into your skin then
twisted into the bone to remove the aspirate. You may
feel pressure when the second needle is inserted into the
bone and rotated to remove the solid sample. See Figure
6. Some people have pain while the samples are being
removed and your skin may be bruised afterward.
If you have a solitary plasmacytoma, a tissue biopsy may
be done to remove a sample for testing. The sample is
often removed with a needle. This can be done either
with a fine-needle aspiration or a core needle biopsy. A
fine-needle aspiration uses a very thin needle to remove
a small sample from the mass. A core needle biopsy
uses a larger needle to collect a larger sample of tissue.
For a tissue biopsy, an imaging test may be used to
guide the needle through the skin and into the mass.
At the lab
The pathologist may do several tests on the biopsy
samples, such as:
• Genetic testing for abnormal genes.
• Staining of marrow and fat pad for amyloid.
Amyloid is an abnormal protein found in people with
myeloma cells that make too many light chains.
The free light chains combine with substances in
the blood, which causes them to clump together
to make amyloid. Amyloid can be deposited in
organs such as the heart and kidneys. The buildup
of amyloid, called amyloidosis, can cause organ
damage. To check for amyloid, the pathologist can
test bone marrow or fat from just under the skin of
the belly, called the fat pad.