It is not a cancer, but it does increase the risk ofmultiple myelomaand sometimes other blood malignancies.
It causes the production of multiple copies of an abnormal protein in your blood.
Around 3% of adults over the age of 50 have MGUS, and this percentage increases with age.
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Symptoms
MGUS is asymptomatic, though people with MGUS may have a somewhat increased risk of infections.
Causes
To understand MGUS, youll need to know a little about your immune system.
Certain immune cells, called plasma cells, make specific proteins called antibodies.
These antibodies are important for fighting many different types of infections.
That is called anM proteinor paraprotein.
Sometimes, a group of identical (monoclonal) plasma cells starts producing large amounts of these M proteins.
These M proteins might not cause any problems, as long as there arent too many of them.
In MGUS, the numbers of these M proteins are relatively low.
There are plenty of normal plasma cells that can do their usual jobs.
However, sometimes, MGUS precedes a situation in which larger amounts of M proteins are produced.
At that point, a person doesnt have MGUS but a true blood cancer.
Types of MGUS
You have different subtypes of antibodies in your body.
These antibodies have somewhat different structures and functions.
One group of antibodies is the IgM group.
There are other different subgroups of antibodies as well.
There are three main different types of MGUS.
These are IgM MGUS, non-IgM MGUS, and light chain MGUS.
These different types of MGUS have a somewhat different risk of developing into a blood cancer.
They also pose an increased risk of different types of blood cancers.
The most common kind of MGUS is the non-IgM pop in.
Non-IGM MGUS has the potential to turn into multiple myeloma.
For non-IgM MGUS, the risk of developing a blood malignancy is about 0.5% a year.
In other words, every year you have about a 1% chance of developing a blood malignancy.
IgM MGUS has a risk of developing into a condition called Waldenstrom macroglobulinemia.
Theres a chance it might lead to a condition called light-chain multiple myeloma.
Diagnosis
People often have MGUS for many years before it is detected.
By one estimate, on average people have had MGUS for around 10 years before it is diagnosed.
Most often, clinicians first become concerned about MGUS from tests that were run for other medical conditions.
But these might indicate that MGUS or another potential blood problem needs to be investigated.
In other cases, your clinician might be concerned about MGUS because of another medical condition.
For example, some kinds ofamyloidosisare like this.
As always, your clinical history and healthcare provider exam provide key diagnostic clues.
Testing
To truly diagnose MGUS, you will need some laboratory tests.
These can help diagnose MGUS and also rule out other medical conditions.
These initial tests may also provide helpful information about the punch in of MGUS that you have.
That can be important, since it gives information about your future risk of developing a serious blood cancer.
Depending on the situation, additional tests might be needed.
For example, some people may need bone imaging tests orbone marrow biopsy tests.
A sample is usually taken from the hip.
They dont have any evidence that their organs have been damaged.
In some cases, your regular healthcare provider will handle your diagnosis.
However, you might be referred to a hematologist who will handle your care.
This may be more likely if you have a higher risk variety of MGUS.
Instead, they might have a related condition called smoldering multiple myeloma.
This condition is very similar to MGUS.
In smoldering multiple myeloma, higher concentrations of M proteins, clonal plasma cells, or both are present.
However, smoldering myeloma doesnt have any of the symptoms or organ damage that can happen with multiple myeloma.
Smoldering multiple myeloma carries a higher risk of progression to multiple myeloma than MGUS does.
Management
No treatment is needed for MGUS.
For example, you might need blood tests about six months after your initial diagnosis.
Depending on the situation, you might continue to need monitoring after that.
If you have a low risk MGUS, you might only need monitoring for a limited time.
Its important to get this monitoring, if its recommended.
One of the most serious potential problems from MGUS is the increased risk of multiple myeloma.
However, early diagnosis of multiple myeloma might help reduce disease complications and extend your lifetime.
Through monitoring, you might be able to treat the disease in its earliest stages.
These might include fatigue, nerve or bone pain, weight loss, or night sweats.
Call your healthcare provider’s office to check-in.
MGUS doesnt usually go away, and it usually requires monitoring.
But the good news is that it is more of a risk factor than an actual medical issue.
Most people with MGUS dont go on to have problems from multiple myeloma or other types of blood cancer.
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