Tuesday 16 June 2020

Myeloma 101

Can I take this for granted?
Sex crime 1984 - Eurythmics

... KFLC = 101 ...

Another teleconsultation with the doctor. Hospital appointments by phone are vastly preferable, as long as there’s nothing much to discuss. I hope this is a change that we can retain long after covid.


Roon 101, Rachel Whiteread (2003)
A cast of a now-destroyed room at Broadcasting House,
where Orwell once worked, and which supposedly
inspired the idea of Room 101 in the novel 1984.
My light chains are down again. A light chain score of 100 would have been my most optimistic aspiration for the outcome of the transplant. Instead, at Day +100 the results were pretty poor, and I was warned to expect to be back in treatment within months. But since then, my myeloma has unexpectedly retreated: KFLC = 250 in December; 160 in March; 130 at the end of April; 101 on 8th June. In some ways this response is even better coming after a delay, as it’s still on a downward trend. I don’t want to jinx myself by imagining next time’s score... but any further drop would compare with the absolute best response I've ever had.

I didn't waste either of our time on the phone asking why it's happening, or whether it will continue. I know that no-one knows. Still, I can approximate some rough prognostics. I might have a few years space, rather than just a few months. Of course, there’s no certainty - it could all change next week. Still, for now I’m pretty pleased with myself. Forgive me if I’m not overly sympathetic to anyone else’s lockdown blues.

Two nerdy appendices:

1. Why would myeloma levels drop after a delay?
myeloma cells are a type of B cell.
B cells normally produce antibodies;
and light chains are a component of antibodies
I don’t think there’s a definitive answer to that - certainly not one my doctors have offered to me. My assumption is that it’s to do with the hierarchy of cells. We know myeloma manifests in B cells, and also that it must exist in the progenitors that produce B cells. I don’t know if we know exactly how far up the hierarchy of stem cells it goes. I’d imagine it must go quite far up - that would explain why mm is so hard to cure. My assumption is that maybe the transplant has done more damage further up the cell lineage, so it is taking time for the response to work through to light chains - which are a downstream measure. If a population of B cells survived the transplant, but populations further "up" the hierarchy were more affected, then the observed effect "down" at light chain level would be that the reduction is delayed, as myeloma B cells are not replaced.

2. Why am I able to hope for relatively long time before my myeloma rears back up?
Some myelomas are faster than others. The prof told me, long ago, that I should be glad to have slow-to-go-down myeloma, as it is probably also slow-to-come-up. This has seemed to hold true. The key measure - I think - is beta 2 microglobulin level (β2-m or B2M). Higher β2-m indicates faster likelihood of relapse (and worse survival). Mine has always been low, and that’s a positive prognostic indicator (it’s the basis for staging the disease, which is why mine is always “stage 1” despite all the grief). I have plenty of negative prognostics too: the genetics of my myeloma are high risk (del17p); I get problematic levels of bone damage; it’s proved stubborn to treat; and I’ve got through a lot of lines of treatment... But despite all that, it’s probably going to continue to be slow. And slow, when it’s in retreat, is a very good thing!