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19

NCCN Guidelines for Patients

®

:

Waldenström’s Macroglobulinemia, Version 1.2017

2

Testing for WM

Biopsy

If needed, a small sample of tissue from a lymph

node or organ is removed by incisional biopsy,

core biopsy, or FNA (

f

ine-

n

eedle

a

spiration). FNA

uses a thin needle with a syringe to take a sample

of suspicious tissue. The entire lymph node or

abnormal mass of cells (tumor) can be removed

during an excisional biopsy to check for cancer.

Other lymphomas are usually diagnosed this way.

MYD88 (L265P) test

DNA is a chain of chemicals inside cells that contains

coded instructions for making and controlling cells.

Your DNA contains instructions from genes that tell

your cells how to grow and behave. When bone

marrow or other tissue is tested, a lab technician

can look at the DNA to see if there is any specific

mutation (change) with a diagnosis of WM. This

mutation is called MYD88 (L265P). This mutation

is common for this cancer. It is found in more than

90 out of 100 people with WM. It may be helpful in

determining the diagnosis of WM from other cancers

that look like WM. Doctors can also determine if

someone will benefit from a getting a cancer drug

known as ibrutinib.

CXCR4 test

More than 40 types of CXCR4 mutations can be

found in people with WM. CXCR4 mutations are

found in 30–40 out of 100 people with WM. It may

help doctors understand if and when people will

respond to ibrutinib therapy.

Pathology review

The biopsy samples will be sent to a pathologist. A

pathologist is a doctor who’s an expert in examining

cells to find disease. For WM, a hematopathologist

may test for cancer. Hematopathologists are

pathologists who specialize in testing for disease of

the blood and lymph nodes. The hematopathologist

will examine the samples using a microscope to see

which type of cancer it is. He or she will look at the

size, shape, type, and specific features of the cells.

The results of the tests, including those described

next, will be recorded in a pathology report. It may

take a few days to get a copy. It’s a good idea to

keep a copy of your pathology report. Your doctors

will use the results to plan your treatment.

Protein test

For diagnosis, the hematopathologist needs to study

the proteins on the cells’ surface The surface is

called the cell membrane. This technique is called

immunophenotyping. WM has a common pattern or

“signature” of proteins. These proteins the doctor

checks for are sIgM+, CD19+, and CD20+. A small

number of people with WM express CD5, CD10, and

CD23.

Ways to test for these proteins are:

†

†

Flow cytometry

assesses substances

(antigens) on the surface of cells to identify the

type of cells present. Blood or bone marrow will

be passed through a flow cytometry machine.

It uses a dye that reacts to light when checking

for the substances.

†

†

Immunohistochemistry (IHC)

uses a chemical

to find specific cell traits involved in abnormal

cell growth.

Other tests

Other tests can be done before treatment. This

depends on what your doctor decides is necessary.

He or she can do certain tests because of treatment

they plan to give you.

Your symptoms are also considered before

ordering a test. More tests will be done if your

hands or feet react poorly to colder temperatures

(cryoglobulinemia) or show signs of nerve

problems (neuropathy). Symptoms like this will

alert your doctor to test for cryoglobulins or do an

electromyogram to check what nerves have been

affected.