title: Perinatal risk factors for cancer of the esophagus and gastric cardia: a nested case-control study.
abstract: BACKGROUND
  We have previously hypothesized that preterm birth or impaired fetal growth may cause esophageal adenocarcinomas through gastroesophageal reflux early in life. In this study, we aimed to test if there is an association between gestational duration and birth weight on the one hand, and risk of esophageal and cardia adenocarcinoma on the other.
  
  
  METHODS
  We conducted a nested case-control study of 67 cases of esophageal adenocarcinoma and 93 cases of cardia adenocarcinoma, whereas 50 cases of squamous cell carcinoma were studied for comparison. Birth records of cases were traced. Three matched controls per case were randomly selected. Perinatal data were extracted from birth records.
  
  
  RESULTS
  Long gestational duration was associated with a decreased risk of cardia adenocarcinoma (P(trend) = 0.001) and a nonsignificant decreased risk of esophageal adenocarcinoma (P = 0.07), whereas no such association was found for esophageal squamous cell carcinoma (P = 0.96). Birth weight was not associated with risk of any of the studied cancers. Compared with lower maternal age (</=24 years) at giving birth, maternal age of 25 to 29 years were associated with a decreased risk of esophageal adenocarcinoma and squamous cell carcinoma (odds ratio, 0.4; 95% confidence interval, 0.2-0.9 and odds ratio, 0.3; 95% confidence interval, 0.1-0.8, respectively).
  
  
  CONCLUSIONS
  Numerical constraints hamper inference, but our results are somewhat consistent with the idea that future risk of esophageal and cardia cancer may in part be determined already perinatally or in infancy and give some limited support to the hypothesis that timing of birth influences risk.
authors.affiliation: Clinical Epidemiology Unit, Karolinska University Hospital, Solna, M9:01, SE-171 76 Stockholm, Sweden. olof.akre@medks.ki.se
authors.forename: Olof
authors.initials: O
authors.lastname: Akre
authors.forename: Lina
authors.initials: L
authors.lastname: Forssell
authors.forename: Magnus
authors.initials: M
authors.lastname: Kaijser
authors.forename: Ingrid
authors.initials: I
authors.lastname: Norén-Nilsson
authors.forename: Jesper
authors.initials: J
authors.lastname: Lagergren
authors.forename: Olof
authors.initials: O
authors.lastname: Nyrén
authors.forename: Anders
authors.initials: A
authors.lastname: Ekbom
mesh_terms: D000230:Adenocarcinoma; D000368:Aged; D001724:Birth Weight; D002294:Carcinoma, Squamous Cell; D002299:Cardia; D016022:Case-Control Studies; D004938:Esophageal Neoplasms / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000453:epidemiology* / Q000209:etiology; D013548:Sweden / Q000453:epidemiology