Hi Mike,
Blast cells are immature cells. Here is a link to MDS Foundaton's handbook about MDS
http://www.mds-foundation.org/pdf/handbook-english.pdf
You know all statistics about prognosis in MDS were done before the patients were treated with EPO for low red blood cells, Neupogen or similar drugs for low white blood cells, Exjade or similar drugs for iron overload, Revlimid, Vidaza, Dacogen, Epival and other new drugs. Patients today have a better prognosis than 5 years ago

.
Hope your red blood cells and white blood cell counts will continue to be OK!
Kind regards
Birgitta-A