Sharon, I hope this post doesn't confuse you. So you need to know what type of myeloma you have. I am IgG Lambda myeloma. I had a lambda band on my immunofixation until just recently. Immunofixation is a more specific test than the electrophoresis. So it does probably mean you still have a few myeloma cells in your marrow. I believe Darzalex can show a kappa band on immunofixation unless they did the Daratumab specific immunofixation, I don't know how he knows unless your myeloma is Lambda. My patient portal from labquest would say a Daratumab specific immunofixation is recommended to differentiate. But anyway, like I said it took about 5 years for the Lambda band to stop showing up on my immunofixation. It stopped showing up on electrophoresis early on. I am still MRD positive in my bone marrow though. So my Emory PA explained this to me.

Darzalex can show up in the Serum Quantum Immunoglobins blood test as false IgG. See this url
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC72...
See this sentence:
"DARA appears on serum protein electrophoresis (SPEP) and on serum immunofixation (sIFE) as an IgG kappa monoclonal immunoglobulin protein (M-protein), complicating the assessment of the patients’ response to therapy."
So ask your doctor specifically about this.

As Donna and others stated, there are a lot of confusing words used to label the type of myeloma you have (light chain, lambda, etc.). My understanding is cancerous myeloma plasma cells turn into a specific Immunoglobin, either IgG, IgA or IgM. Mine is IgA and my initial IgA when diagnosed was 3552.
The other big indicator in blood tests is the highly used "M-spike" protein. This is a measurement of abnormal proteins measured using a Serum Protein Electrophoresis blood test. It is a very good indicator of abnormal cells with an M-spike (or paraprotein) and typically your blood test will have a commentary from a doctor who analyzed the sample.

So these are probably the 2 best blood tests for determining if you have myeloma cells. BUT, blood chemistry is very complicated, value can go up/down from month to month and abnormalities can be caused by other issues.

So here's the crappy news. The only way to tell if your relapsing is to have another one of those wonderful bone marrow biopsy's.

Good luck, keep and eye on your blood tests and pester your doctor with questions. If he/she cannot/does not answer them, ask for documentation or a person who can.

Complete Depletion of Daratumumab Interference in Serum Samples from Plasma Cell Myeloma Patients Improves the Detection of Endogenous M-Proteins in a Preliminary Study

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7235820/

Definitely prove him wrong!! What happened to a little human compassion? This disease is awful. I’m in remission but still have a lot of off days. I have constant back pain and understand that. But still just don’t feel well some days. Hang in there.. everyone is different!

Get a new oncologist! Your current one has awful bedside manners!! Mine gives me hope & hugs me after each appt.

Wow nice bedside manners not maybe you should try finding a new Oncologist.