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If signs or symptoms suggest that a patient has non-Hodgkin
lymphoma, exams and tests are done to find out for certain if this
disease is present and, if so, to determine the exact type of lymphoma.
Signs and symptoms of non-Hodgkin lymphoma
Non-Hodgkin lymphoma may cause many different signs and
symptoms, depending on its location in the body. In some cases it may
not cause any symptoms until it grows quite large.
Lymph nodes near the skin
Non-Hodgkin lymphoma can affect lymph nodes close to the
surface of the body (such as on the sides of the neck, in the groin or
underarm areas, or above the collar bone), which may be seen or felt as
lumps under the skin. These are often found by the patient, a family
member, or a health care professional. Enlarged lymph nodes are more
often caused by infections than by lymphoma.
Abdomen
Lymphomas in the abdomen may cause the abdomen to become
swollen and tender. This may be due to either a tumor or to large
collections of fluid. When lymphoma causes swelling near the
intestines, the passage of feces may be blocked, which may lead to
abdominal pain, nausea, or vomiting.
Lymphomas of the stomach often cause pain in the stomach,
nausea, and reduced appetite.
Chest
When lymphoma starts in the thymus or lymph nodes in the
chest, it may press on the nearby trachea (windpipe), which can cause
coughing or trouble breathing.
The superior vena cava (SVC) is the large vein that carries
blood from the head and arms back to the heart. It passes near the
thymus and lymph nodes inside the chest. Lymphomas in this area may
push on the SVC, which can cause the blood to back up in the veins.
This is known as SVC
syndrome. It can cause swelling (and sometimes a
bluish-red color) in the head, arms, and upper chest. It can also cause
trouble breathing and a change in consciousness if it affects the
brain. The SVC syndrome can be life-threatening, and requires treatment
right away.
Brain
Lymphomas of the brain, called primary brain lymphomas,
can cause headache, trouble thinking, weakness in certain parts of the
body, personality changes, and sometimes seizures.
Skin
Lymphomas of the skin can be seen and felt. They often appear
as extremely itchy, red or purple lumps or nodules under the skin. (For
more details, see the separate document Lymphoma of the Skin.)
General symptoms
Along with symptoms and signs resulting from local effects of
cancer growth, non-Hodgkin lymphoma can cause generalized symptoms,
such as:
- unexplained weight loss
- fever
- drenching night sweats (enough to soak clothing)
Doctors sometimes call these B symptoms. The
presence of B symptoms is often found in more rapidly growing
lymphomas.
Diagnosing non-Hodgkin lymphoma by a biopsy
Many of the symptoms of non-Hodgkin lymphoma are not specific
enough to say for certain if cancer is present. Most of these symptoms
can also be caused by non-cancerous problems, like infections, or by
other kinds of cancers.
For example, enlarged lymph nodes are more often caused by
infections than by non-Hodgkin lymphoma. Because of this, doctors often
wait a few weeks to see if they remain large. Sometimes they prescribe
antibiotics to see if they cause the nodes to shrink.
If the nodes continue to grow or stay the same size, either a
small piece of a node or, more commonly, the entire node is removed for
viewing under the microscope and for other lab tests. This procedure is
called a biopsy.
A biopsy may be needed right away if the size, texture, or
location of the node or the presence of other symptoms strongly
suggests cancer is present. But a delay in diagnosis of a few weeks is
not likely to be harmful in most instances. The exception to this would
be a very rapidly growing lymphoma.
Types of biopsies used to diagnose
non-Hodgkin lymphoma
A biopsy is the only way to diagnose non-Hodgkin lymphoma.
There are several types of biopsies. Doctors choose which one to use
based on the unique aspects of each person's situation.
Excisional or
incisional biopsy: This is the most common type of biopsy
if lymphoma is suspected. In this procedure, a surgeon cuts through the
skin to remove either the entire node (excisional biopsy) or a small
part of a large tumor (incisional biopsy). If the node is near the skin
surface, this is a simple operation that can often be done with local
anesthesia (numbing medicine). But if the node is inside the chest or
abdomen, general anesthesia is used (where the patient is asleep). This
method almost always provides enough of a sample to diagnose the exact
type of non-Hodgkin lymphoma. It is preferred, if it can be done
without too much discomfort to the patient.
Fine needle
aspiration (FNA) or core needle biopsy: In an FNA biopsy,
the doctor uses a very thin needle attached to a syringe to withdraw
(aspirate) a small amount of tissue from a tumor mass. A core needle
biopsy uses a larger needle to remove a slightly larger piece of
tissue.
For an enlarged node near the surface of the body, the doctor
can aim the needle while feeling the node. If the tumor is deep inside
the body, the doctor can guide the needle using a computed tomography
(CT) scan or ultrasound (see discussion of imaging tests later in this
section).
A needle biopsy does not require surgery, but in many cases it
may not remove enough of a sample to make a definite diagnosis.
Advances in lab tests (discussed later in this section) and the growing
experience of many doctors have improved the accuracy of this
procedure.
Most doctors do not use needle biopsies to make a diagnosis of
lymphoma, but they may use FNA in patients already diagnosed to confirm
that an enlarged lymph node or organ in another area also contains
lymphoma. FNA can also be used to diagnose cancers that spread to nodes
from other organs and to identify nodes swollen by infection that don't
need to be removed.
Other types of biopsies
These procedures may be done to diagnose lymphoma, but they
are more often done to help stage (determine the extent of) a lymphoma
that has already been diagnosed.
Bone marrow
aspiration and biopsy: These procedures are often done
after lymphoma has been diagnosed to help determine if it has reached
the bone marrow. The two tests are often done at the same time. The
samples are usually taken from the back of the pelvic (hip) bone,
although in some cases they may be taken from the sternum (breast bone)
or other bones.
In bone marrow aspiration,
you lie on a table (either on your side or on your belly). After
cleaning the skin over the hip, the doctor numbs the area and the
surface of the bone with local anesthetic, which may cause a brief
stinging or burning sensation. A thin, hollow needle is then inserted
into the bone and a syringe is used to suck out a small amount of
liquid bone marrow (about 1 teaspoon). Even with the anesthetic, most
patients still have some brief pain when the marrow is removed.
A bone marrow biopsy
is usually done just after the aspiration. A small piece of bone and
marrow is removed with a slightly larger needle that is twisted as it
is pushed down into the bone. The biopsy may also cause some brief
pain. Once the biopsy is done, pressure will be applied to the site to
help stop any bleeding.
Lumbar puncture
(spinal tap): This test looks for lymphoma cells in the
cerebrospinal fluid (CSF), which is the liquid that bathes the brain
and spinal cord.
For this test, the patient may lie on their side or sit up.
The doctor first numbs an area in the lower part of the back over the
spine. A small, hollow needle is then placed between the bones of the
spine to withdraw some of the fluid.
Most people with lymphoma will not need this test. But doctors
may order it for certain types of lymphoma or if a person has symptoms
that suggest the lymphoma may have reached the brain.
Pleural or
peritoneal fluid sampling: Spread of lymphoma to the
chest or abdomen can cause fluid to build up. Pleural fluid (inside the
chest) or peritoneal fluid (inside the abdomen) can be removed by
placing a hollow needle through the skin into the chest or abdomen. The
doctor uses a local anesthetic to numb the skin before inserting the
needle. The fluid is then withdrawn and looked at under the microscope
to check for lymphoma cells.
Lab tests on biopsy samples to diagnose and
classify lymphoma
All biopsy samples and fluids are looked at under a microscope
by pathologist (a doctor with special training in recognizing cancer
cells), who studies the appearance, size, and shape of the cells and
how the cells are arranged. This may reveal not only if the person has
a lymphoma, but also what type of lymphoma it is. Because the diagnosis
of lymphoma can be tricky, it helps if the pathologist specializes in
diseases of the blood.
Pathologists can sometimes tell which kind of lymphoma a
patient has by looking at the cells, but usually other types of tests
are needed to confirm the diagnosis.
Immunohistochemistry
In this test, a part of the biopsy sample is treated with
special antibodies (man-made versions of immune system proteins) that
attach only to specific molecules on the cell surface. These antibodies
cause color changes, which can be seen under a microscope. This test
may be helpful in distinguishing different types of lymphoma from one
another and from other diseases.
Flow cytometry
Like immunohistochemistry, this test looks for certain
substances on the outside surface of cells that help identify what
types of cells they are. But this test can look at many more cells than
immunohistochemistry.
For this test, a sample of cells is treated with special
antibodies that stick to the cells only if certain substances are
present on their surfaces. The cells are then passed in front of a
laser beam. If the cells now have antibodies attached to them, the
laser will cause them to give off light, which can be measured and
analyzed by a computer. Groups of cells can be separated and counted by
these methods.
This is the most commonly used test for immunophenotyping
-- classifying lymphoma cells according to the substances (antigens) on
their surfaces. Different types of lymphocytes have different antigens
on their surface. These antigens may also change as each cell matures.
Flow cytometry can help determine whether lymph node swelling
is due to lymphoma, some other cancer, or a non-cancerous disease. It
has also become very useful in helping doctors determine the exact type
of lymphoma so that they can select the best treatment.
Cytogenetics
This technique allows doctors to evaluate the chromosomes
(long strands of DNA) in the lymphoma cells. The cells are looked at
under a microscope to see if the chromosomes have any translocations
(where part of one chromosome has broken off and is now attached to
another chromosome), as happens in certain types of lymphoma. Some
lymphoma cells may have too many chromosomes, too few chromosomes, or
other chromosome abnormalities. These changes can help identify the
type of lymphoma.
Cytogenetic testing usually takes about 2 to 3 weeks because
the lymphoma cells must grow in lab dishes for a couple of weeks before
their chromosomes are ready to be viewed under the microscope.
Molecular genetic studies
These tests look more closely at lymphoma cell DNA. They can
detect most changes that are visible under a microscope in cytogenetic
tests, as well as others that can't be seen.
Fluorescent in
situ hybridization (FISH): FISH is similar to cytogenetic
testing. It uses special fluorescent dyes that only attach to specific
parts of chromosomes. FISH can find most chromosome changes (such as
translocations) that can be seen under a microscope in standard
cytogenetic tests, as well as some changes too small to be seen with
usual cytogenetic testing.
FISH can be used to look for specific changes in chromosomes.
It can be used on regular blood or bone marrow samples. It is very
accurate and can usually provide results within a couple of days, which
is why this test is now used in many medical centers.
Polymerase chain
reaction (PCR): PCR is a very sensitive DNA test that can
also find some chromosome changes too small to be seen under a
microscope, even if very few lymphoma cells are present in a sample.
These tests can also detect certain genes that have been
"turned on" and are contributing to the lymphoma cells' abnormal
growth. As researchers learn more about lymphomas, these may become
even more important.
Other lab tests
Blood tests may be used to measure the amounts of certain
types of cells and chemicals in the blood. They are not used to
diagnose lymphoma, but they can sometimes help determine how advanced
the lymphoma is. In patients already known to have lymphoma, if the
blood counts are low, it might mean that the lymphoma is growing in the
bone marrow and affecting new blood cell formation. Results of another
blood test that measures levels of lactate dehydrogenase (LDH) will
often be abnormally high in the blood of patients with fast-growing
lymphomas.
Other blood tests can help detect liver or kidney problems
caused by the spread of lymphoma or due to the side effects of certain
chemotherapy drugs. Blood tests can also help determine if treatment is
needed to correct low or high blood levels of certain minerals. Tests
may also be done to make sure blood is clotting properly.
Imaging tests
Imaging tests use x-rays, sound waves, magnetic fields, or
radioactive particles to produce pictures of the inside of the body.
These tests may be done for a number of reasons, including to help find
a suspicious area that might be cancerous, to learn how far a cancer
may have spread, and to help determine if treatment has been
effective..
Chest x-ray
X-rays of the chest are often done to look for enlarged lymph
nodes in this area.
Computed tomography (CT) scan
The CT scan is a type of x-ray that produces detailed,
cross-sectional images of your body. Unlike a regular x-ray, CT scans
can show the detail in soft tissues (such as internal organs). This
scan can help tell if any lymph nodes or organs in your body are
enlarged.
CT scans are useful for looking for lymphoma in the abdomen,
pelvis, chest, head, and neck.
Instead of taking one picture, as does a regular x-ray, a CT
scanner takes many pictures as it rotates around you. A computer then
combines these pictures into detailed images of the part of your body
that is being studied.
Before the scan, you may be asked to drink a contrast solution
and/or get an intravenous (IV) injection of a contrast dye that helps
better outline abnormal areas in the body. You may need an IV line
through which the contrast dye is injected. The injection can cause
some flushing (a feeling of warmth, especially in the face). Some
people are allergic and get hives or, rarely, more serious reactions
like trouble breathing and low blood pressure. Be sure to tell the
doctor if you have ever had a reaction to any contrast material used
for x-rays.
CT scans take longer than regular x-rays. You need to lie
still on a table while they are being done. During the test, the table
moves in and out of the scanner, a ring-shaped machine that completely
surrounds the table. You might feel a bit confined by the ring you have
to lay in when the pictures are being taken.
Spiral CT
(also known as helical CT) is now available in many medical centers.
This type of CT scan uses a faster machine. The scanner part of the
machine rotates around the body continuously, allowing doctors to
collect the images much more quickly than standard CT. This lowers the
chance of blurred images occurring as a result of body movement. It
also lowers the dose of radiation received during the test. The slices
it images are thinner, which yields more detailed pictures.
In some cases, CT can be used to guide a biopsy needle
precisely into a suspicious area. For this procedure, called a CT-guided needle biopsy,
you remain on the CT scanning table while a radiologist moves a biopsy
needle through the skin and toward the location of the mass. CT scans
are repeated until the needle is within the mass. A biopsy sample is
then removed to be looked at under a microscope.
Magnetic resonance imaging (MRI) scan
Like CT scans, MRI scans provide detailed images of soft
tissues in the body. But MRI scans use radio waves and strong magnets
instead of x-rays. The energy from the radio waves is absorbed by the
body and then released in a pattern formed by the type of body tissue
and by certain diseases. A computer translates the pattern into a very
detailed image of parts of the body. A contrast material called
gadolinium is often injected into a vein before the scan to better see
details. The contrast material usually does not cause allergic
reactions.
MRI scans are very helpful in looking at the brain and spinal
cord.
MRI scans take longer than CT scans -- often up to an hour.
You may have to lie inside a narrow tube, which is confining and can be
distressing to some people. Newer, more open MRI machines may be
another option. The MRI machine makes loud buzzing and clicking noises
that you may find disturbing. Some places provide headphones or
earplugs to help block this out.
Ultrasound
Ultrasound uses sound waves and their echoes to produce a
picture of internal organs or masses. For this test, a small,
microphone-like instrument called a transducer is placed on the skin
(which is first lubricated with a gel). It emits sound waves and picks
up the echoes as they bounce off the organs. The echoes are converted
by a computer into a black and white image that is displayed on a
computer screen.
Ultrasound can be used to look at lymph nodes near the surface
of the body or to look inside your abdomen for enlarged lymph nodes or
organs such as the liver and spleen. It can also detect kidneys that
have become swollen because the outflow of urine has been blocked by
enlarged lymph nodes. (It can't be used to look at organs or lymph
nodes in the chest because the ribs block the sound waves.)
This is an easy test to have done, and it uses no radiation.
You simply lie on a table, and a technician moves the transducer over
the part of your body being looked at.
Positron emission tomography (PET) scan
For a PET scan, glucose (a form of sugar) containing a
radioactive atom is injected into the blood. Because cancer cells in
the body grow rapidly, they absorb large amounts of the radioactive
sugar. A special camera can then create a picture of areas of
radioactivity in the body.
PET scans can help tell if an enlarged lymph node contains
lymphoma or is benign. The picture is not finely detailed like a CT or
MRI scan, but it provides helpful information about your whole body.
PET scans can be used to tell if a lymphoma is responding to
treatment. Some doctors will repeat the PET scan after 1 or 2 courses
of chemotherapy. If the chemotherapy is working, the lymph nodes will
no longer take up the radioactive glucose. PET scans can also be used
after treatment in helping decide whether an enlarged lymph node still
contains lymphoma or is merely scar tissue.
Recently, newer devices have been developed that combine the
PET scan with a CT scan (PET/CT scan). This allows the doctor to
compare areas of higher radioactivity on the PET scan with the more
detailed appearance of that area on the CT.
Gallium scan
For this test, a solution containing slightly radioactive
gallium is injected into a vein. It is attracted to lymph tissue in the
body. A special camera can then detect the radioactivity, showing the
location of the gallium. This test can find lymphoma tumors in bones
and other organs.
This test is not used as much now as in the past, as many
doctors may do a PET scan instead. It can still sometimes be useful in
finding areas of lymphoma that the PET scan may miss. The gallium scan
will not detect most slow-growing lymphomas but will find many
fast-growing (aggressive) lymphomas. It can also help distinguish an
infection from a lymphoma when the diagnosis is not clear.
Bone scan
For bone scans, a different radioactive substance (technetium)
is used. After it is injected, it travels to areas of the bone that are
damaged. Lymphoma often causes bone damage, and a bone scan will find
it. But a bone scan may also pick up non-cancerous problems, such as
arthritis and fractures. This test is not usually done unless a person
is having bone pain or has lab test results that suggest the lymphoma
may have reached the bones.
Last Medical Review: 07/17/2009 Last Revised: 07/17/2009
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