We conclude that DEK-CAN molecular monitoring by RQ-PCR in t(6;9) malignancies is a useful tool for individual patient management and that molecular negativity is indispensable for survival, but should not be a prerequisite for allografting in this rare, poor prognosis, subset of AML..     ///    DEK-CAN molecular monitoring of myeloid malignancies could aid therapeutic stratification..     ///    We used a DEK-CAN real-time quantitative (RQ)-PCR strategy to analyze 79 retrospective and prospective samples from 12 patients.     ///    Five patients reached DEK-CAN negativity (sensitivity 10(-5)).     ///    "All four cases in CCR with adequate follow-up (median 18.5 months, range 13--95) demonstrate persistent molecular negativity, whereas all seven patients with persistent DEK-CAN positivity died at a median of 12 months from diagnosis (range 7--27). "