Freelite®
More about Freelite®
Freelite is the trade name for a test that measures the
Why is the ratio
· The ratio is important because the
What is
amount of free light chains in the blood
important?
free light chain levels can increase
Freelite®?
if there are kidney problems, or
What are
· Free light chains are the light chains of myeloma
sometimes for other reasons
free light
protein (M-Protein)
· Since both light chain levels will
chains?
· These light chains can be kappa ()
rise in this situation, any additional
or lambda () in type
increase in the light chains produced
· They are called "free" light chains because they
by the myeloma will give an abnormal
are not bound to the rest of the immunoglobulin
ratio. This is an important double-
(antibody) molecule that may be produced by
check. An abnormal ratio means there
myeloma cells, which are malignant plasma cells.
is still extra light chain production
There is a separate test for total or "bound" light
coming from the myeloma
chains that is not useful in myeloma testing.
What does it mean
· This is the best situation:
· Myeloma cells typically produce extra light chains
not used to manufacture a full immunoglobulin
if the light chain
no extra light chain production
molecule. Sometimes myeloma cells only produce
levels and the ratio
from the myeloma
free light chains, and this type of myeloma is called
are all in the normal
no kidney problems
"Bence Jones" or "light chain" myeloma
range?
· This is part of the definition of
stringent complete response (sCR)
Normal
The Freelite test consists of two assays:
when there is CR and a normal
assay
· one for free kappa light chains
Freelite level and ratio
ranges
Normal range: 3.319.4 mg/L
· one for free lambda light chains
If both light chain
· This usually means that the myeloma
and ratio
Normal range: 5.7126.3 mg/L
levels are increased,
is in remission, but that kidney
but the ratio is normal?
function is not normal
The ratio of free kappa to lambda is then calculated:
Normal range: 0.261.65
How accurate is the Freelite test?
If the free kappa / free lambda ratio is outside this
· The Freelite assay is a very accurate test that detects very low levels
range and greater than 1.65, then a kappa myeloma
of free light chains
is indicated; conversely, if the ratio is less than 0.26,
· It is extremely important, however, to be aware that there are
a lambda myeloma is indicated. Following diagnosis,
normal fluctuations ( and ) in free light chain levels, especially
the individual light chain levels and the ratio can be
within or close to the normal ranges, i.e., at very low levels
used to monitor the response to treatment
even 2550% changes can occur at these low levels
with serial monitoring, it is important to not overreact and to
Why is the Freelite test used?
discuss all changes/fluctuations/concerns with the treating
· The International Myeloma Working Group (IMWG) and the
physician
NCCN Guidelines* recommend the use of serum free light chain
· Progressive increase in free light chain levels is of the greatest
assays in the initial diagnostic work up of suspected myeloma
concern, particularly sequential increases of 50% in successive
patients to increase the diagnostic sensitivity
measurements
· In patients with non- or oligo- (non-secretory) myeloma, there is
How can my doctor order the test?
not enough M-Protein in blood or urine to measure using protein
· The Freelite test is readily available in most hospitals and clinics
electrophoresis serum (SPEP) or urine (UPEP). Approximately
performed either within the center or by a central testing laboratory.
7080% of myeloma patients with non-secretory disease can be
It is important that your doctor specify "free" light chains when
tracked, however, using the Freelite test which can thus be used
ordering the test to ensure that the correct test is run.
for accurate monitoring of the tumor marker
· Results from different laboratories can be slightly different.
· Since the Freelite test is very sensitive, very low levels of myeloma
Check which laboratory was used for testing.
tumor burden can be detected and monitored. For Bence Jones
If there is a change in the results, it is important to check the units
myeloma patients normally tracked using UPEP (24-hour urine
used: (for example mg/L or otherwise) as results can be expressed
collection) the Freelite test can be used for low-level disease
differently, creating a 10-fold difference in lab values.
monitoring to assess maximum response and even possible
early relapse. (Studies are underway to determine if the serum
Is Freelite covered by insurance?
Freelite test can substitute for 24-hour UPEP testing in monitoring
· Freelite is reimbursed by Medicare and most private insurers
Bence Jones myeloma.)
it is a relatively inexpensive test which can be used, for example,
as a part of a monthly myeloma testing package.
* referenced with permission from the NCCN Clinical Practice Guidelines in Oncology
(NCCN Guidelines) for Multiple Myeloma V.I. © 2010 National Comprehensive Cancer Network, Inc.
All Rights Reserved. www.nccn.org
INTERNATIONAL
Freelite® is a registered trademark of The Binding Site Group, Ltd., Birmingham, UK
MYELOMA FOUNDATION
800.452.CURE (2873)
in the US & Canada
818.487.7455
International Myeloma Foundation
12650 Riverside Drive, Suite 206
North Hollywood CA 91607-3421
myeloma.org
818.487.7455
myeloma.org
"Until there is a cure, there is the IMF."