Childhood cancer in relation to parental race and ethnicity: a 5-state pooled analysis.
BACKGROUND
Children of different racial/ethnic backgrounds have varying risks of cancer. However, to the authors' knowledge, few studies to date have examined cancer occurrence in children of mixed ancestry.


METHODS
This population-based case-control study examined cancer among children aged <15 years using linked cancer and birth registry data from 5 US states from 1978 through 2004. Data were available for 13,249 cancer cases and 36,996 controls selected from birth records. Parental race/ethnicity was determined from birth records. Logistic regression analysis was used to examine the association of cancer with different racial/ethnic groups.


RESULTS
Compared with whites, blacks had a 28% decreased risk of cancer (odds ratio [OR], 0.72; 95% confidence interval [95% CI], 0.65-0.80), whereas both Asians and Hispanics had an approximate 15% decrease. Children of mixed white/black ancestry also were found to be at decreased risk (OR, 0.71; 95% CI, 0.56-0.90), but estimates for mixed white/Asian and white/Hispanic children did not differ from those of whites. Compared with whites: 1) black and mixed white/black children had decreased ORs for acute lymphoblastic leukemia (OR, 0.39 [95% CI, 0.31-0.49] and OR, 0.58 [95% CI, 0.37-0.91], respectively); 2) Asian and mixed white/Asian children had decreased ORs for brain tumors (OR, 0.51 [95% CI, 0.39-0.68] and OR, 0.79 [95% CI, 0.54-1.16], respectively); and 3) Hispanic and mixed white/Hispanic children had decreased ORs for neuroblastoma (OR, 0.51 [95% CI, 0.42-0.61] and OR, 0.67 [95% CI, 0.50-0.90], respectively).


CONCLUSIONS
Children of mixed ancestry tend to have disease risks that are more similar to those of racial/ethnic minority children than the white majority group. This tendency may help formulate etiologic studies designed to study possible genetic and environmental differences more directly.
Chow
Eric J
EJ
Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA. ericchow@u.washington.edu
Puumala
Susan E
SE
Mueller
Beth A
BA
Carozza
Susan E
SE
Fox
Erin E
EE
Horel
Scott
S
Johnson
Kimberly J
KJ
McLaughlin
Colleen C
CC
Reynolds
Peggy
P
Von Behren
Julie
J
Spector
Logan G
LG
D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data; D017668:Age of Onset; D044466:Asian People / Q000706:statistics & numerical data; D002648:Child; D002675:Child, Preschool; D005006:Ethnicity; D006630:Hispanic or Latino / Q000706:statistics & numerical data; D006801:Humans; D008423:Maternal Age; D009369:Neoplasms / Q000453:epidemiology* / Q000208:ethnology*; D010290:Parents; D012737:Sex Factors; D044465:White People / Q000706:statistics & numerical data