Table 1.

Demographic characteristics of study subjects

	RQ-PCR rise greater than 3-fold, n = 101	No RQ-PCR rise greater than 3-fold, n = 49	P	All patients, N = 150
Median age, y (range)	51.1 (16-79)	47.8 (23-74)	.45	50.6 (16-79)
Sex, % male	56	47	.15	53
Median months from leukemia diagnosis to imatinib start (range)	21 (0-161)	6 (0-155)	.03	17 (0-161)
Patients with “early” CML diagnosis, fewer than 6 mo before imatinib, %	26	53	.002	35
Baseline diagnosis of chronic-phase CML/ accelerated-phase/blast crisis, %	79/20/1	90/10/0	.31	82/17/1
Median months of follow-up, after imatinib (range)	48 (11-80)	40 (7-75)		46 (7-80)
Median no. of laboratory monitoring visits (range)	9 (2-21)	7 (2-18)	.76	8 (2-21)
Median months between monitoring visits (range)	3.9 (1.6-8.3)	4.0 (2.3-7.8)	.66	3.9 (1.6-8.3)
CCR ever achieved, %	58	82	.003	66
MCR (< 35% Ph) never achieved, %	24	10	.051	19
Imatinib treatment failure, % (primary resistance)*	60	37	.11	53
MMR ever achieved, %	39	57	.019	45
Median RQ-PCR log-drop at time of DNA sequencing (range)	0.77 (−1.0 to 2.6)	1.8 (−0.4 to 5.2)	< .001	1.0 (−1.0 to 5.2)
CCR (MCR) at time of sequencing, %	28 (49)	58 (75)	.007	37 (57)
Complete hematologic response at time of sequencing, %	80	90	.17	83
Kinase domain mutation, no. (%)	43 (43)	10 (20)	.010	53 (35)

RQ-PCR indicates real-time quantitative reverse-transcription polymerase chain reaction; CML, chronic myeloid leukemia; CCR, complete cytogenetic response; MCR, major cytogenetic response; and MMR, major molecular response.

^*Defined, per European LeukemiaNet (ELN) criteria,³ as failure to reach MCR (< 35% Ph-positivity) by 12 months or CCR by 18 months.