Risk factors of breast cancer in Mexican women.
OBJECTIVE
To investigate the association between family history (FH) of neoplasia, gyneco-obstetric factors and breast cancer (BC) in a case-control study. In cases, to analyze those variables in relation with early onset of BC, the manner of detection (self-examination, prompted by pain, or casual), the size of tumor, and the elapsed time to seek medical attention.


METHODS
Data from 151 prevalent BC cases and 235 age-matched controls were analyzed by multiple logistic regression, to assess the influence of BC risk factors.


RESULTS
Ten per cent of patients and 1% of controls had first-degree relatives (FDR) with BC. Family history of FDR with BC (OR, 11.2; 95% CI 2.42-51.92) or with gastric or pancreatic cancer (OR, 17.7; 95% CI 2.2-142.6) was associated with BC risk. Breastfeeding at or under 25 years of age was protective against BC (OR, 0.40; 95% CI 0.24-0.66). The manner of tumor detection did not influence its size at the time of diagnosis.


CONCLUSIONS
Our study confirms that FH of BC and/or of gastric or pancreatic carcinoma are risk factors for BC, while lactation at 25 years of age or earlier is protective.
Calderón-Garcidueñas
A L
AL
Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma de Nuevo León (UANL), México.
Parás-Barrientos
F U
FU
Cárdenas-Ibarra
L
L
González-Guerrero
J F
JF
Villarreal-Ríos
E
E
Staines-Boone
T
T
Barrera-Saldaña
H A
HA
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000453:epidemiology / Q000235:genetics*; D016504:Breast Self-Examination / Q000706:statistics & numerical data; D016022:Case-Control Studies; D005192:Family Health; D005260:Female; D006801:Humans; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D012307:Risk Factors; D018401:Sample Size; D012959:Socioeconomic Factors