[murphy1]

M-spike "too small to quantify" - does it mean anything?

by murphy1 on Tue Apr 03, 2018 9:54 pm

My total protein dropped from 8.3 to 7.6 in six months and my electrophoresis from 6 months ago reported back monoclonal band ID'd by immunofixation IgG kappa and monoclonal IgA kappa. It was reported back this time that the M-spike quantity is too small to determine g/dl.

All other values for electrophoresis stayed the same or got better.

Does this indicate anything, or does this fluctuate over time?

[Multibilly]

Re: M-spike "too small to quantify" - does it mean anything?

by Multibilly on Wed Apr 04, 2018 8:45 am

Hi Murphy1,

It sounds like you have a biclonal gammopathy. What's your exact diagnosis (MGUS, smoldering or symptomatic myeloma)? Also, what were the values of your two M-spikes and kappa and lambda free light chain values over time since you were first diagnosed? It's really hard to comment on your current situation without first having a bit more history on your diagnosis and lab numbers.

[blueblood]

Re: M-spike "too small to quantify" - does it mean anything?

by blueblood on Wed Apr 04, 2018 10:18 am

Murphy1,

I have gotten a report "may be present in original location" I assumed it was just a blip in the graph, too small to quantify. I have had them come and go. Obviously, I like it when they 'go.'

Upon closer inspection, I noticed there was a slight correlation between who actually signed the test results. I don't know if any of this matters the least.

Craig

[Foundry738]

Re: M-spike "too small to quantify" - does it mean anything?

by Foundry738 on Wed Apr 04, 2018 12:59 pm

M-spike values have some subjectivity to them, especially when they are very low or if they are not at the far right of the graph. Therefore, I wouldn't worry about single reports about absence or presence and just monitor trends. In the paper listed below, the authors have proposed an alternate method of determining M-spike that might be less subjective:

Zhang, S, et al., "Improved Method for Estimating M-Spike Proteins in Serum Protein Electrophoresis," Journal of Clinical & Experimental Pathology, June 26, 2014 (full text of article)

It has examples of measuring large spikes and how those numbers might vary, but imagine trying to decide where and how to place the lines denoting the spike when there is no obvious elevation of a curve due to very low levels of the monoclonal immunoglobulin(s).

[Mark Pouley]

Re: M-spike "too small to quantify" - does it mean anything?

by Mark Pouley on Wed Apr 04, 2018 2:15 pm

When I saw a similar test result, I was told it meant there was some mono­clonal protein detected, but the amount was simply "too small to quantify." I took it as a good sign that treat­ments had re­duced the cancer burden. My next results stated that "previously identified monoclonal component currently not detected."

Certainly, ask your doctors, but I take the results as a good sign for you that things are headed in the right direction.