Characterization of Pediatric Acute Lymphoblastic Leukemia Survival Patterns by Age at Diagnosis

Table 2

Hazard risk of mortality associated with age at diagnosis in pediatric ALL patients (1973–2009 SEER dataset) in an univariable Cox proportional hazard model.

Variables	Hazard ratio (HR)	95% C.I.
Age at diagnosis (yrs)
<1	1.00	—	Reference
1–4	0.18	0.15, 0.20	<0.0001
5–9	0.26	0.22, 0.30	<0.0001
10–14	0.44	0.38, 0.51	<0.0001
15–19	0.69	0.59, 0.80	<0.0001
Sex
Female	1.00	—	Reference
Male	1.29	1.20, 1.39	<0.0001
Race
Caucasian	1.00	—	Reference
AA	1.44	1.27, 1.62	<0.0001
Primary tumor sites
1	1.00	—	Reference
≥2	1.18	0.92, 1.52	0.1950
Immunophenotype
T-cell	1.00	—	Reference
B-cell, B-precursor	0.57	0.49, 0.65	<0.0001
Radiation
No	1.00	—	Reference
Yes	1.66	1.53, 1.79	<0.0001
Year of diagnosis
1973–1977	1.00	—	Reference
1978–1982	0.70	0.61, 0.80	<0.0001
1983–1987	0.56	0.49, 0.65	<0.0001
1988–1992	0.38	0.33, 0.44	<0.0001
1993–1997	0.32	0.28, 0.36	<0.0001
1998–2002	0.29	0.26, 0.33	<0.0001
2003–2007	0.24	0.21, 0.27	<0.0001
2008-2009	0.19	0.14, 0.25	<0.0001

C.I.: confidence interval.