When your Metamyelocytes are high it can mean that your bone marrow has become infiltrated by myelofibrosis or metastases.
The Metamyelocytes are cells that are undergoing granulopoiesis that are derived from a myelocyte, and leading to a band cell.
It is characterized by the appearance of a bent nucleus, cytoplasmic granules, and the absence of visible nucleoli.
When the Metamyelocytes are high it can sometimes mean you have a blood disease or possible cancer but not always.
Your doctor should let you know exactly what is going on and may want to perform some other tests to determine if anything else is wrong.
If the levels of Metamyelocytes are not too high then you might not have any blood disease or cancers of the blood.
But it's a good idea to get more tests done to be sure.