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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 are
easily 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 non-Hodgkin
lymphoma.
Abdomen: When
the lymphoid tissue inside the abdomen is involved, the abdomen can
become tender, painful, and/or swollen. 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 discomfort or abdominal pain. The pressure or blockage can also
cause 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
irritate or compress 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 in the face and arms and a
bluish-red coloration of 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 and
moving 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 to 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 produce
generalized symptoms, such as:
- unexplained weight loss
- fever
- drenching night sweats (enough to soak clothing)
- severe itchiness
Doctors sometimes call these generalized effects B symptoms. The
presence of B symptoms is often related to the presence of more rapidly
growing lymphoma cells.
Diagnosing Non-Hodgkin Lymphoma
by a Biopsy
The diagnosis of lymphoma may be delayed because 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 the
antibiotics cause the nodes to shrink.
If the node continues to grow or stays the same size, either a
small piece of the 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 imediately if the size, texture, or
location of the node or the presence of other symptoms strongly
suggests cancer is present. But there is no evidence that a delay in
diagnosis of a few weeks is 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 biopsy procedures, and the doctor's choice is based
on the unique aspects of each person's situation.
Excisional or
incisional biopsy: This is the most common type of biopsy.
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 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 biopsy: In a fine needle aspiration ( 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. 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 while viewing a computed tomography
(CT) scan (see discussion of imaging tests in this section).
The main advantage of FNA is that it does not require surgery.
The disadvantage is that in many cases the thin needle cannot remove
enough of a sample to make a definite diagnosis. But advances in lab
tests (discussed later in this section) and the growing experience of
many doctors with FNA have improved the accuracy of this procedure.
Most doctors will use FNA in patients already diagnosed with
lymphoma to confirm that an enlarged lymph node or organ in another
area also contains lymphoma. FNA is also very useful in diagnosing
cancers that spread to nodes from other organs and in identifying 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: Bone marrow samples are obtained
from a bone marrow aspiration and biopsy - two tests that 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 (breastbone) or other bones.
In bone marrow aspiration,
you lie on a table (either on your side or on your belly). After
cleaning the area, the skin over the hip and the surface of the bone
are numbed 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 (about 1/16 inch in
diameter and 1/2 inch long) 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.
These tests can be used for the initial diagnosis and for
staging (to see how far the cancer has spread).
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 near the
spine. A small needle is then placed between the bones of the spine to
withdraw some of the fluid.
Lab Tests Used to Diagnose and
Classify Non-Hodgkin Lymphoma
All biopsy samples and fluids are looked at under a microscope
by pathologist (a doctor with special training in recognizing cancer
cells). The pathologist looks at 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 is
trained and experienced in diagnosing lymphomas.
Pathologists who specialize in diagnosing lymphoma can often
tell which kind of lymphoma a patient has, but sometimes this exam does
not provide a definite answer. In these cases, one or more of the
following lab tests may be needed.
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 non-Hodgkin
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 these 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 non-Hodgkin lymphoma, some other cancer, or a non-cancerous
disease. It has also become very useful in helping doctors determine
the exact type of non-Hodgkin lymphoma so that they can select the best
treatment.
Cytogenetics
This technique allows scientists to evaluate the chromosomes
(long strands of DNA) in the lymphoma cells. Scientists look at cells
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. In
addition to translocations, some lymphoma cells may have too many
chromosomes, too few chromosomes, or other abnormalities of the
chromosome. These changes can be used to help identify the type of
lymphoma.
Molecular Genetic Studies
Tests of lymphoma cell DNA 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) is similar to
cytogenetic testing. It can find most translocations that are visible
under a microscope in standard cytogenetic tests, as well as some
translocations too small to be seen with usual cytogenetic testing. It
uses special fluorescent dyes that only attach to specific parts of
chromosomes. 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.
Very sensitive DNA tests such as polymerase chain reaction
(PCR) can also find translocations too small to be seen under a
microscope, even if there are very few lymphoma cells 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. In the future, as researchers learn more about lymphomas, these
may become the most useful tests for determining what kind of lymphoma
is present.
Other Lab Tests
Blood tests may be used to measure the amounts of certain
types of cells and chemicals in the blood. While they are not used to
diagnose lymphoma, they can be helpful in deciding how advanced the
lymphoma is. In patients already known to have lymphoma, if the blood
counts are low, it might indicate that the lymphoma is growing in the
bone marrow and damaging normal blood cell production. Results of
another blood test that measures levels of lactate dehydrogenase or
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 cells 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 are used to find and look at tumors inside the
body. These tests are an important part of staging (determining if and
how much the cancer has spread) non-Hodgkin lymphoma.
Chest X-ray
X-rays of the chest are often done to look for enlarged lymph
nodes in this area.
Computed Tomography
The computed tomography (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. A CT scan is 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.
Often after the first set of pictures is taken, you will
receive an intravenous (IV) injection of a dye, or radiocontrast agent,
which helps better outline structures in your body. You may also be
asked to drink 1 to 2 pints of a solution of contrast material. This
helps outline the intestine so that it is not mistaken for tumors if
your doctor is looking for abnormal areas in your abdomen. A second set
of pictures is then taken.
The IV injection of contrast dye 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.
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 fine needle biopsy
sample (tiny fragment of tissue) or a core needle biopsy sample (a thin
cylinder of tissue about ½-inch long and less than 1/8-inch in
diameter) is then removed to be looked at under a microscope.
Magnetic Resonance Imaging
Magnetic resonance imaging (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 might be injected, just as with CT scans, but is used less
often.
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 upset
people who are afraid of enclosed spaces. Newer, open MRI machines can
help with this if needed. The MRI machine makes loud buzzing noises
that you may find disturbing. Some places provide headphones to block
this out.
Positron Emission Tomography
Positron emission tomography (PET) scans involve injecting
glucose (a form of sugar) that contains a radioactive atom 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 scans can help pinpoint the exact
location of the lymphoma.
Gallium Scan
During this procedure, the radiologist injects a small dose of
radioactive gallium 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. These tests can find tumors that might be
non-Hodgkin lymphoma in bones and other organs.
The gallium scan will not detect most slow-growing lymphomas
but will recognize many fast-growing (aggressive) lymphomas. It was
used before PET scans were available and can still be useful in finding
lymphoma deposits that the PET scan may miss. It is also useful in
distinguishing infections from lymphomas when the diagnosis is not
clear.
Bone Scan
For bone scans, a different radioactive substance 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 will also pick up non-cancerous problems, such as arthritis
and fractures. This test is not generally used in the early staging
process for non-Hodgkin lymphoma.
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 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 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.
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.
Revised: 08/29/2007
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