Hi Kristen,
As Zoe told you they look for blasts in the bone marrow (hopefully they are less than 5 %) and in the blood (hopefully about 0,01 %). It is the % in the bone marrow they use for staging.
As Zoe wrote it is not always possible to aspirate when you have severe fibrosis (they have never been able to aspirate from my bone marrow due to fibrosis - this makes BMP almost painless since it is the aspiration that hurts).
BMP in the sternum is not so common - many years ago all BMP:s were done in the sternum but the patients have less complications when the BMP is done in the christa in the back.
I got two BMP at dx and then a third one 3 years after dx - I have been transfusion dependent since dx.
If the EPO is more than 500 at dx Aranesp has hardly ever any effect. Aranesp gives the best results in patients with EPO less than 200. Aranesp is EPO and if your own kidneys make EPO it is no use to give more (my EPO was more than 800 at dx and I never got Aranesp).
Do take care of your mother's platelets - there is a warning list at the PDAS forum:
http://www.pdsa.org/itp-information/itp-warnings.html
There are many drugs that decrease the platelets (look out for pain killers) and then many kinds of food can increase bleeding like garlic, onion, chocolate, blueberries and so on. My platelet count was 65 at dx and is now 40-50 with some small bleedings (petechia) around the eyes as only symptom.
You know low age (less than 65) and no other diseases give your mother a better prognosis
.
Kind regards
Birgitta-A