Table 5:

Summary of MRD Relation to EFS from a Large Children's Oncology Group Study

MRD Timing	Sample	MRD+ Cut-point	N Analyzed	Variables in Analysisa	HR for EFS
Day 8	PB	> 0.01%	1,946	End-induction MRD, NCI risk	1.51b
End of induction	BM	> 0.01%	2,086	group, favorable trisomies, day-8 MRD, TEL-AML1 translocation, Day-8 M1 marrow	4.31b
End of consolidation	BM	> 0.01%	1,470	End-induction MRD, NCI risk group, End-consolidation MRD	2.25b

Abbreviations: BM, bone marrow; EFS, event-free survival; HR, hazard ratio; M1, bone marrow with < 5% leukemic blast cells; MRD, minimal residual disease; N, sample size; NCI, National Cancer Institute; PB, peripheral blood; TEL-AML1, favourable genetic translocation.

^aStepwise Cox regression analyses.

^bStatistically significant at the level of P < .001.

Source: Borowitz et al, 2008.⁴²