Well, there won't be much of a good answer until someone trys to force your system to do something. Without giving your marrow a chance to make cells, the answers are limited.
They are essentially three answers for us, one of them fits, one will end up fitting for you.
First, rule out:
1. Other cancer(s)/myleoproliferative disorders(s). We've been dealing with these low counts a long time, this has been done to everyones satisfaction. Well, maybe not the patient, she still worries something awful is going on in there. The first indication that this was NOT the case was response to no TKI making those numbers climb, even a little. After that, the grower making neutrophils go through the roof even in the presence of Gleevec.
2. An extremely rare syndrome in which your body attacks its' own neutrophils. There is a test for this. Takes a buncha blood. Only the Red Cross does the test, you can only do it on certain days, and they draw the blood a certain amount of time before having it picked up. Is complex, can get all fluxored up by something as simple as traffic delaying the blood picker upper dude, and is frustrating because there are now three parties, you, the dox, and the Red Cross. Don't trust it to the local LabCorp or National, not worth trying. We did it for The Mrs, it was negative, but it was the only thing they had not ruled out, way far out in left field whack nuts as it was, we are glad they did it.
This would be indicated by withdrawing TKI and moving the grower shots farther apart. ANC measurements would chart like that road going into Yosemite from northern Nevada, a great ride if you ever get out there. We didn't have any suspicion of this at all, our onc just sorta pulled this idea out of his butt, he's been doing this blood stuff a long time I guess.
3. TKI. We all know about that one, our situation is that.
The answer is only one of the above for the most part. Either marrow not making them, or they are being destroyed out in the peripheral. Don't know for certain either until they force you to make cells, and I don't know why they are letting you sit there like that.
If my Mrs got that low they would have hospitalized her until they knew what was going on, of that I am certain.
Good luck with it Michael. I hate this happening to you and I really wish they would just shoot you up and get them going.