What further tests have been done to confirm IgM MGUS?

Question

Hi doctor,

I am 46 years old, and I was diagnosed with IgM MGUS at a low concentration last month. I am concerned about the bone marrow results, which are expected to arrive next week. My GP referred me to a hematologist. I do not have the symptoms of WM, but hematologists suggest a bone marrow biopsy and a CT scan to exclude lymphoplasmacytic lymphoma with a twenty percent chance. I am really scared and worried.

Kindly help.

Answer 1

Hi,

Welcome to icliniq.com.

Based on the reports, you have IgM MGUS (monoclonal gammopathy of undetermined significance). But we need to confirm it by doing a bone marrow biopsy, and it should be less than 10 percent clonal lymphoplasmacytic or plasma cells in the bone marrow. About one percent of people with MGUS can develop multiple myeloma every year. So there is a very low risk of developing the frank disease.

The only issue I can see is your age, and MGUS occurs after 70 years of age. Less than two percent develop MGUS at 40 years of age. This makes it so that your age is not so common to have this disease. You need to do skeletal imaging to rule out any bone lesions, and it is seen in multiple myeloma and not in MGUS.

I hope this helps.

Answer 2

Hi,

Welcome back to icliniq.com.

There are many close names. MGUS, smoldering myeloma, multiple myeloma, and lymphoplasmacytic lymphoma come under a diagnosis called plasma cell dyscrasias. They are differentiated by monoclonal spike, clinical symptoms, and bone marrow biopsy. If it is 10 percent without symptoms, it becomes smoldering myeloma, and if it is less than 10 percent with symptoms, then it becomes multiple myeloma.

The special class called lymphoplasmacytic lymphoma has similar findings, but there is lymph node enlargement, weakness, and fatigue related to anemia. It is differentiated from the above by doing a special test called flow cytometry and the MYD88 L265P mutation. It occurs commonly at 70 years of age. IgM (immunoglobulin M) has an association with all these diseases, and your case matches with IgM MGUS, and it requires a follow-up. You need to do a bone marrow biopsy soon. Try to have a follow-up with the results of it.

I hope this helps.

Answer 3

Hello,

Welcome back to icliniq.com.

Thanks for asking this question. There are two different things. Let me clarify for you.

I said, for IgM MGUS, there should be no more than 10 percent of cancer cells.
If it is more than 10 percent of cancer cells, then it can be smoldering myeloma, Multiple myeloma, or WM (Waldenstrom macroglobulinemia, or lymphoplasmacytic lymphoma).
> 10 percent cancer cells but without anemia, hypercalcemia, elevated creatinine, or bony lesions = smoldering myeloma.
> 10 percent of cancer cells with anemia, hypercalcemia, elevated creatinine, or bony lesions = smoldering myeloma.

WM is special and rare (one to two percent of total blood malignancies), commonly seen in individuals over 60 years, and has plasma cell-like cells called lymphoid and plasmacytoid cells. However, it is commonly associated with anemia, hypercalcemia, similar to multiple myeloma, and may present other findings like splenomegaly, hepatomegaly, etc. Treatment for both WM and multiple myeloma is similar.

In your case, you are mostly asymptomatic, except for urticaria. There is no anemia, hypercalcemia, or elevated creatinine. For bone lesions, we need to do a low-dose CT (computed tomography). Your age is also young. Moreover, I have not come across data indicating a 10 to 20 percent chance of discovering lymphoplasmacytic lymphoma. I understand that this is a frustrating period. I do not want you to go into panic mode. Please consider meditation; it helps for sure. Let us wait for the BM (bone marrow) result. I am hopeful it turns out to be IgM MGUS only. I am sorry this is too much information; hope this helps to relax you a bit.

Stay positive and stay in touch.

Thank you.

Answer 4

Hello,

Welcome back to icliniq.com.

Very happy to see you again. Congratulations on having a normal BM. You must be thrilled, and I can imagine that. If I were in your place, I would go ahead and do a CT scan. I know sometimes knowing less is better, but in my understanding, the earlier we know, the better prepared we can be to take action if needed. Moreover, who knows, your CT scan might turn out to be completely normal. So, it all depends on your wishes. I would not force you into it and leave the decision up to you.

Once again, you have been very thoughtful and have always asked relevant questions. Let me know how you feel in a couple of months. I am here to help you to the best of my ability.

Thank you.

Regards.