[Multibilly]

Albumin level in ISS staging - which one?

by Multibilly on Mon Oct 27, 2014 9:01 am

I have one albumin level listed in my metabolic panel and another one listed in my SPEP. The two values always differ a fair amount on my ongoing tests. As an example, my last albumin SPE was 4.5g g/dL (ref range: 3.4 - 5.1 g/dL) and my albumin level from my metabolic panel was 3.4 g/dL (ref range: 3.4 - 5.0 g/dL).

1. Why do these two different albumin levels always differ so much?
2. Which of these two values is used for ISS staging purposes?

[Anna F]

Re: Albumin level in ISS staging - which one?

by Anna F on Mon Oct 27, 2014 11:34 am

Hi there,

Thanks for your help with my previous question! Perhaps this will help with yours. I ran across this post earlier.

Right now, my dad only has his SPE results, so I'm waiting on the CBC but, like you, wonder which one counts for the staging system. I haven't found an answer for that and have looked everywhere. I see the CBC is more accurate, but that doesn't necessarily mean it's the one the staging is based on. And considering the numbers are so different, I feel that's a really valid question.

For now, here's the post I saw:

The reason for the difference is the following:

The SPE value for albumin is INDIRECT, because it is based only on the direct total protein value from the Metabolic Panel. This is why the sum of all the values from the SPEP equals the total protein value. Check it out. It is not a coincidence.

So if your DIRECT protein value is higher on a particular blood draw day so will be the INDIRECT albumin value (and all other SPE values for that matter). The SPEP albumin value is therefore deemed less accurate and less reliable for this reason.

In contrast, the albumin value in the Metabolic Panel has its own DIRECT measure­ment method and so is deemed more accurate and reliable.

[Dr. Prashant Kapoor]

Re: Albumin level in ISS staging - which one?

by Dr. Prashant Kapoor on Tue Oct 28, 2014 1:14 am

Hello Multibilly,

You pose an important question yet again. The original ISS study used albumin from either SPEP or comprehensive metabolic panel, whichever one was available at the time of diagnosis of active myeloma for a patient, and therefore could not specify the albumin value a clinician should use, particularly if results from both methods were available.

We attempted to answer this question in 2008, about three years after the Greipp Staging System / ISS was published in the Journal of Clinical Oncology. Here is the reference and link:

P Kapoor et al., "Clinical Impact of Discordance in Serum Albumin Measurements on Myeloma International Staging System," Journal of Clinical Oncology, 2008 (full text pdf)

Although, the comprehensive metabolic panel albumin is more accurate and SPEP tends to overestimate albumin in patients with higher M-spikes, one could actually use either of those values for staging. If the use of two albumin values obtained from different methods leads to discordant staging (for example, stage 1 using chemistry method, and stage 2 using SPEP method for albumin measurement, or vice versa), one could use either of the 2 stages, since the survival of such patients lies somewhere between the two stages but is not statistically different from survival of either true stage 1 or stage 2 patients. Note that stage 3 is completely unaffected by albumin levels.

Lastly, it should be remembered that patients with smoldering multiple myeloma should not be staged with ISS as this staging system was originally designed and validated only in patients with symp­tomatic myeloma.

Hope this helps answer your question to a degree.

With best wishes,
Prashant Kapoor

[Multibilly]

Re: Albumin level in ISS staging - which one?

by Multibilly on Tue Oct 28, 2014 7:19 am

Thanks for the very complete answer Dr. Kapoor! It's indeed nice to have access to all the great medical experts on this forum.

Note that this question came to mind as I was referring to my own labs when trying to help a symptomatic patient with her questions regarding ISS staging.