Risk of breast cancer in families with cleft lip and palate.
OBJECTIVE
To test whether female subjects in families with cleft lip and/or palate (CL/P) have an increased risk of breast cancer.


METHODS
By using the Danish Facial Cleft Registry, we identified female subjects with CL/P, mothers of children with CL/P, and sisters to CL/P cases for the Danish birth cohorts 1911-1975. These subjects were compared with a 5% random sample of these cohorts regarding the incidence and age of onset for breast cancer registered in the Danish Hospital Discharge Register 1977-2005.


RESULTS
Examining 48,404 person-years for 1809 female CL/P cases (49 breast cancer cases) and 212,795 person-years for 7935 female relatives (188 breast cancer cases), we found no increased breast cancer risk for either CL/P cases (hazard ratio [HR], 1.23; 95% confidence interval (CI), 0.92-1.63), mothers of children with CL/P (HR, 0.93; 95% CI, 0.80-1.08), or sisters of CL/P cases (HR, 0.94; 95% CI, 0.55-1.60), nor was there any significant differences in age of onset.


CONCLUSIONS
Both epidemiological and genetic studies have suggested common etiological factors for breast cancer and CL/P. However, in this population-based study we were not able to confirm a general increase in the risk of breast cancer among female subjects in families with CL/P.
Children's Hospital, University of Iowa, Iowa City, USA.
Alexander
A
Dietz
Dorthe Almind
DA
Pedersen
Rune
R
Jacobsen
George L
GL
Wehby
Jeffrey C
JC
Murray
Kaare
K
Christensen
D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D002971:Cleft Lip / Q000235:genetics*; D002972:Cleft Palate / Q000235:genetics*; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D016016:Proportional Hazards Models; D012042:Registries; D018570:Risk Assessment; D018709:Statistics, Nonparametric