Beta 2 Microglobulin

[Willowbug]

After 4 years in W & W my blood tests showed a new test called Beta 2 Microglobulin with a 2.4 rating in a (0.0. - 2.5 ) range. Can someone explain the need for this test and if there is cause for concern. Thanks!

[AussieNeil Administrator]

That's an acceptable result - it's within the reference range after all.Beta 2 Microglobulin (B2M) was established by M D Anderson as an indicator of how active CLL was. A correlation between the value and likely life expectancy was established, but the correlation was done prior to the era of targeted therapy we have now. A higher result correlated with a probable shorter life expectancy.

Neil

[Willowbug in reply to AussieNeil]

Thank you for the information, I appreciate it!

[LuzyCLL]

My new hematologist did a “Free Kappa Lambda Ratio” test. I looked it up and found;

A kappa free light chain test is a blood test that measures the levels of a certain type of protein in your blood. Your plasma cells (a type of white blood cell that fights infections and illnesses) make light chains. Light chains usually link up with other proteins called heavy chains. Together, they make immunoglobulins (antibodies) and help your immune system work properly. Providers call unlinked proteins in your blood “free light chains.” Your blood contains two types of free light chains: kappa and lambda light chains. It’s normal to have some of both. But some people have abnormally high or low levels of one or both types of free light chains in their blood. Free light chains outside of the normal range might mean you have a plasma cell disorder. The test is also used to monitor existing plasma cell disorders.

My result showed a slightly high free kappa lambda ratio. Plasma cell disorder?

[AussieNeil Administrator in reply to LuzyCLL]

It's not at all unusual to have a kappa to lambda light chain ratio outside the normal limit, either above or below, when we have CLL. That's because, as you noted, the light chains are part of the immunoglobulin structure, which is incorporated as the receptor part of the B cell receptor, prior to the B cell churning out immunoglobulins in the mature, plasma cell form. There's around a 50% chance of B cells incorporating either a kappa or lambda light chain, which naturally applies to CLL cells too. So when we end up with a large, monoclonal CLL population, which eventually undergoes apoptosis, you are likely to end up with an excess of either kappa or lambda light chains in your blood from your CLL.

Neil

[lexie]

When tested at diagnosis by my CLL specialist at age 64 my B2M was 2.7 which appears out of range. He said higher numbers are expected as age increases and he considered 2.7 perfectly normal despite the lab's range. I quit worrying about it.

[Willowbug]

Thank you Lexie!

[mikec11]

B2M has also been added to international scoring for evidence of advancements in staging. I believe it is when it above 3.5 if memory serves.

[mikec11]

CLL International Prognostic Index (CLL-IPI)

The CLL-IPI combines genetic, biochemical and clinical parameters to categorize patients into four prognostic risk groups. Five independent prognostic factors were identified:

TP53 deleted or mutated = 4 points

Unmutated IGHV = 2 points

Serum beta-2 microglobulin concentration > 3.5 mg/L = 2 points

Rai Stage I - V or Binet Stage B - C = 1 point

Patient age > 65 years = 1 point

The CLL-IPI provides treatment recommendations by risk group based on the points system.

CLL-IPI Category Risk Score Treatment Recommendations

Low Risk 0-1 Do not treat

Intermediate Risk 2-3 Do not treat unless the disease is highly symptomatic

High Risk 4-6 Treat unless the patient is asymptomatic

Very High Risk 7-10 If the decision is made to treat, use novel agents or treatment in a clinical trial rather than chemotherapy

[wizzard166]

Hey Willowbug

Your Beta 2 Microglobulin Level of 2.4 would be pretty good, so at least on that one issue I'd be fairly happy.

This small protein is made by many types of cells, including CLL cells. The protein can be measured through a blood chemistry test. High levels of beta-2 microglobulin (B2M) are associated with a type of CLL that is harder to treat. When looking at different levels of B 2 M a general consensus is that your level is a mild calm progression of CLL. Our illness is considered to be Aggressive when the B2M level goes over 4.0.

My B2M level back in February 2020 was 3.4, and that was two years after my original diagnosis. The tests I have from original diagnosis in March 2018 don't mention B2M. I decided to get in with one of the top CLL Specialists in the Country at Dana Farber in February 2020, and her first testing included B2M. My progression since that first test at Dana Farber is as follows:

Name

Standard Range

2/18/20 9/8/20 4/13/21 9/28/21 3/29/22 9/20/22 3/21/23

3.4 4.0 4.2 4.0 5.0 4.8 5.6

So I supposed I should be quite anxious at my last reading of 5.6 in March 2023; however, my Specialist didn't get excited so I'm staying calm too. I think the main thing appears to be with my Specialist is my Hemoglobin and Platelet levels. When our disease gets more aggressive, they look for Hemoglobin and Platelets to go down to dangerous levels. Mine have stayed so far at the Border of Low Normal for Hemoglobin, and a bit below Normal for Platelets. My next visit in Boston is first week in September, so we'll see how she feels then. My attitude has always been to stay out of treatment if possible, so I'm still feeling calm. When I here it is likely time to start treatment, thats when I'll get nervous.

Carl

[rafew]

One thing to remember is that B2M is a non-specific test. [not specific to CLL] a high B2M may indicate other infections. The normal range at the Mayo lab is Normal range: 1.21 - 2.70 mcg/mL My numbers range between 3>5.46