Is there data to support holding the 5th cycle of intensification for an AML patient with good prognosis and a history of significant infections and/or prolonged count recovery?  

Great question. The answer is kind of. The COG studies AAML03P1 and AAML0531 gave 5 chemotherapy cycles to patients who did not go to transplant in first remission, but we know that some patients did not get the 5th cycle. As you suggested, most of the time the reason for stopping after 4 cycles was...