[Greg H]

Jx3,

The pathologist will do a differential (the breakdown of bloods cells by type) on the marrow aspirate, but what you're really looking for in the BMB results is the answer to why your Dad's counts are low.

So, the first question will be whether the marrow has the expected number of cells in it or whether it has more than expected (hypercellular) or fewer than expected (hypo cellular). Most MDS folks are hypercellular; aplastic anemia is hypocellular; but some folks with MDS are hypocellular, too.

Next stop is blasts. Blasts are immature white cells. In normal marrow they make up 1-5% of the cells. More than that, and you have excess blasts, which is not a good sign. More than 20 or 30% blasts, and it starts to look like leukemia.

Next stop is dysplasia: a fancy word for messed up cells. The pathologist will look at all three blood lines (lineages): reds, whites, and platelets. Cells go through a multistage process in the marrow, from the original stem cells, through a variety of "progenitor" cell types, and then onto the final product, namely, the blood cells that circulate in the body. The pathologist will be looking for messed up cells anywhere in this process. Your Dad might have dysplasia in the white cell line only, or in whites and platelets, or in reds only, or in all three.

If he has dysplasia, then he'll mostly likely be diagnosed with MDS. How many lines are messed up has some significance for treatment decisions, so its something that you and your doctor will pay attention to.

Next stop is cytogenetics. This has two parts: karotype and FISH.

Karotype involves actually growing out a few bone marrow cells until they are ready to divide, and then killing them in order to spread out all the chromosomes and look at them. This is where you find out if your Dad has any chromosomal abnormalities. Whether he has them, and which ones, can affect both prognosis and the recommended course of treatment.

FISH is a fancy way to for specific chromosomal abnormalities that are known to be common in bone marrow failure diseases. Not all BMBs involve FISH.

So that's what you can expect in terms of data.

Give a shout if that raises any other questions.

Take care!

Greg