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Health update

Published on 37 Comments on Health update

Nutshell summary: Good news!

Long, complicated explanation: Buckle up for this one. No doctors were involved in this analysis.

As you know, for years I've been getting M-protein results to check the level of multiple myeloma in my bone marrow. This is done via an SPEP test—Serum Protein Electrophoresis. A successful treatment of my cancer would mean that the M-protein level was "undetectable." Not completely gone, but so low the SPEP test couldn't detect it.

I always assumed this meant an SPEP result of 0. But no: I finally got tired of never getting an explanation of how this stuff really works so I looked up the clinical literature myself. In the relevant units, it turns out that SPEP can only detect M-protein down to about 0.10.

But there's more. I've also been getting a second test all along: Serum Immunofixation. It's a binary test (normal/abnormal) so I've never paid any attention to it. Obviously I've been abnormal ever since I was diagnosed.

Not anymore. It turns out that immunofixation is only accurate down to a level of about 0.05. Below that the cancer level is undetectable.

Now, as you might recall, the CAR-T procedure I had last April can produce a range of outcomes. The best outcome is "complete," which turns out to mean a cancer level that's undetectable by both SPEP and immunofixation. Conversely, if you're below the SPEP level but still above the immunofixation level, your outcome is "partial complete."

That's where my test results have been for months. But this month something changed in the immunofixation results. Instead of "IgG Kappa monoclonal gammopathy"—i.e., multiple myeloma—the result was "Band of restricted mobility of IgG Kappa. Consider retesting if clinically indicated." This suggests that the immunofixation result is right on the edge of being undetectable. Here's a chart:

September was the last time I got an SPEP result. Now, in January, I seem to be very near to not getting an immunofixation result either. If this is true, it means I've finally reached the fabled "complete" response from the CAR-T procedure. It took eight months instead of six weeks, but in the end it came through.

Now, it's worth noting that no doctor has confirmed this for me. In the case of my general oncologist I think it's because he's not familiar enough with CAR-T to know these details. In the case of my transplant physician, I imagine he knows but just never felt like explaining in detail.

So that's that. It's good news no matter what, and if my amateur interpretation is correct it's very good news. The next step would be a test for MRD—Minimal Residual Disease—which is more sensitive than either SPEP or immunofixation. No one has suggested this yet, probably because I was nowhere near needing it before now. Maybe someday.

In any case, who knows? The fact that it took so damn long to reach this level might mean it will also take a very long time before it starts to go up again. My multiple myeloma has always been fairly slow reacting. Check back with me in 2028 or so and we'll know.

37 thoughts on “Health update”

  4. Eastvillager

    Yeah! This is great news! Put a cat on your lap and let the purrs help.
    BTW it’s Friday afternoon where are the cat pics????

  7. ColBatGuano

    Given the only recent adoption of a CAR-T treatment for MM, I think it is going to be awhile before doctors have a handle on what a "cure" looks. Before this, MM was treated with things that only slowed the disease so there is no experience with a complete response. Glad to hear you fall in this group.

  9. Pittsburgh Mike

    It does sound like very good news to me. And it's certainly good that your numbers keep going down, months after the treatment!

  11. iamr4man

    Hummmm, looks like you may be around long enough to make that HSR train ride from L.A. to San Francisco after all! Great news!

  16. samboo

    I am surprised you have not been MRD tested yet - I was diagnosed in 2015 and have had 5 bone-marrow biopsies and - from the samples collected - 2 MRD tests that can detect myeloma down to the molecular level - way more accurate than the blood markers.

    The MRD tests are expensive, but there is one test that I have had (https://www.clonoseq.com/myeloma/) that offers it at no cost if insurance denies it.

    Regardless ... congrats on heading in the right direction.

  17. zaphod

    Kevin, it looks like your procedure was a success after all. Good. And it is likely that what goes down slowly might also take its time in going up, if it ever does again.

    You will be around for many more years, if you don't get involved in an accident with one of those AI cars they are testing on the roads.

  22. ddoubleday

    Hearty congratulations. Looks like we'll have you to kick around in the comments section for a long time!

    I know this was a trial, but the treatment as you've described it must be enormously expensive. I wonder if it will ever be a treatment that people can just get with insurance?

  29. pjcamp1905

    "Now, it's worth noting that no doctor has confirmed this for me."

    Those guys? Don't let them rain on the party.

    Doctors are like that Lil Abner character and his thundercloud.

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