<prompt> Non specific esterase is positive in all the categories of AML exceptM3M4M5M6  <response>: Non specific esterase on cytochemistry is strongly positive in M5acute monocytic leukemia- Schilling type and M4acute myelomonocytic leukemia -Naegeli type which have monocytic component.It is also positive in M3acute promyelocytic leukemia.But non specific esterase is negative in M6acute erythroleukemia-Di Guglielmos syndrome,which shows positive for Periodic acid-Schiff. Reference:Textbook of pathology-Harsh Mohan,6th edition,page no:362. 