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06/10/2009
2006 Consensus guidelines for the management of women with abnormal cervical cancer screening tests.
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04/10/2009
SERUM FREE LIGHT CHAINS, A New Test for Patients with Monoclonal Gammopathies
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SERUM FREE LIGHT CHAINS, A New Test for Patients with Monoclonal Gammopathies
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02/04/2009
Article Answers Questions Re: Testing for GC/Chlamydia in Liquid Based Pap Collection Vials
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 Serum Free Light Chains April 2009 SERUM FREE LIGHT CHAINS A New Test for Patients with Monoclonal Gammopathies Free light chains of immunoglobulin in urine, known as Bence Jones protein and originally described in 1848, were the very first biochemical tumor marker used to diagnose cancer. Today, the measurement of serum free light chains (SFLC) is changing the way patients with monoclonal gammopathies are diagnosed and followed. This is occurring because of the recent development of highly specific antibodies purified to react only with SFLC and not with light chains bound to heavy chains. The measurement of SFLC offers several advantages over urine studies and virtually eliminates the need for urine studies in patients with monoclonal gammopathies. Serum is easier to collect than urine, does not require concentration, and is easily stored. The ratio of kappa to lambda free light chains in serum is little affected by renal function. Since SFLC have a very short half-life (just a few hours as opposed to 21 days for IgG), they are an excellent way to monitor therapy in patients with monoclonal gammopathies or to detect recurrence of disease. SFLC also demonstrate prognostic value in patients who have monoclonal gammopathy of undetermined significance (MGUS). RML is pleased to bring the ability to determine SFLC to our clients and their patients. As of April 20, 2009, this test will be available locally. We will be changing our myeloma screening panel to include the following elements: serum protein electrophoresis (SPE), serum immunofixation electrophoresis (SIFE), and SFLC with kappa/lambda ratio. This panel will accurately diagnose 99 to 100% of patients with myeloma, primary amyloidosis, and MGUS. SPE and SFLC alone will detect nearly all patients with myeloma and amyloidosis, but fewer patients with MGUS. Urine studies (both protein electrophoresis and immunofixation electrophoresis) will still be available, but are felt to offer only supporting evidence of disease, and are probably not clinically relevant unless there is also evidence of disease in the serum. Since levels of SFLC can be affected by renal function or by bone marrow suppression, it is the free kappa/lambda ratio which is actually more important than the individual level of either free kappa or free lambda in the original diagnosis of a monoclonal gammopathy. A short interpretive note will be included when you receive a report on SFLC. Note that the SIFE profile, which currently includes immunoglobulins (G, A, and M), total kappa, and total lambda, will be discontinued. However, individual tests will continue to be available. These include SPE, SIFE, immunoglobulins (G, A, and M) and SFLC. Total kappa and lambda testing will be discontinued. If you have any questions about this new test or the change in our myeloma panel, please contact Dr. Jim Niewenhuis at 969-6161 x 6918 or Ken Vanden Bosch at 969-6161 x 6932. |
