title: Infant breastfeeding and the risk of childhood lymphoma and leukaemia.
abstract: BACKGROUND
  A protective effect of breastfeeding on childhood lymphoma has been indicated but supportive evidence is limited.
  
  
  METHODS
  Data from a population-based case-control study of childhood cancer in Shanghai, including 82 lymphoma cases and 159 acute leukaemia cases and their age- and sex-matched community controls, were analysed.
  
  
  RESULTS
  After adjustment for potentially confounding variables, a slight, although non-significant, reduction in risk of lymphoma was observed among children who were breastfed as infants versus those who were not (odds ratio [OR] = 0.69; 95% CI: 0.3-1.7). The reduction was somewhat greater for children who had been breastfed longer and appeared to pertain primarily to Hodgkin's disease and to cases diagnosed before the age of 6 years. As expected, there was no reduction in risk of acute leukaemia associated with breastfeeding.
  
  
  CONCLUSIONS
  Although providing neither strong support for nor refuting the study hypothesis, these data suggest that if breastfeeding does reduce the risk of lymphoma, its protective effect among Chinese children is likely modest in magnitude and concentrated in certain subgroups defined by length of breastfeeding, age at diagnosis and histological subtype of cancer.
authors.affiliation: Department of Epidemiology, Shanghai Cancer Institute, People's Republic of China.
authors.forename: X O
authors.initials: XO
authors.lastname: Shu
authors.forename: J
authors.initials: J
authors.lastname: Clemens
authors.forename: W
authors.initials: W
authors.lastname: Zheng
authors.forename: D M
authors.initials: DM
authors.lastname: Ying
authors.forename: B T
authors.initials: BT
authors.lastname: Ji
authors.forename: F
authors.initials: F
authors.lastname: Jin
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000367:Age Factors; D000704:Analysis of Variance; D001724:Birth Weight; D001942:Breast Feeding; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D015986:Confounding Factors, Epidemiologic; D003627:Data Interpretation, Statistical; D005260:Female; D006689:Hodgkin Disease / Q000453:epidemiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007938:Leukemia / Q000453:epidemiology*; D008223:Lymphoma / Q000453:epidemiology*; D008228:Lymphoma, Non-Hodgkin / Q000453:epidemiology; D008297:Male; D008423:Maternal Age; D016017:Odds Ratio; D012307:Risk Factors; D012737:Sex Factors; D012959:Socioeconomic Factors; D013997:Time Factors