title: [Hormonal replacement therapy and breast cancer. A case-control study].
abstract: OBJECTIVE
  Breast cancer is the second more frequently neoplasia in the woman and the first cause of mortality after 35 years old. It is considered a multifactorial illness, since is influenced for genetic, dietary and endocrine factors. Among these, hormonal replacement therapy (HRT) have been assigned benefits effect, as well as risks to increase the breast cancer incidence, because presence of estrogens receptor in the neoplasia cells makes think that the estrogens and other sexual hormones constitute a factor promoter of this cancer.
  
  
  OBJECTIVE
  The objective of this study was to determine the association of HRT as risk factor in the incidence of breast cancer, in women from oncology-gynecological service.
  
  
  METHODS
  Was carried out this descriptive study in patients that used HRT, considering as cases patients with breast cancer confirmed by hystophatological study and controls the patients without breast cancer. To statistical analysis took mean occurrence using the momios reason (MM), with confidence interval of 95% (CI), and chi2 test of Mantel-Haenszel, for a significant value of p < 0.05.
  
  
  RESULTS
  Were included successively 250 patients, in 100 of these were confirmed diagnosis of breast cancer, 60 patients (37.5%) used HRT with mean of 3 years and 40 patients (44.4%) did not use HRT (Cases), the other 150 patients did not have breast cancer, 100 of these used HRT and 50 patients did not use HRT (Control). The statistical analysis showed that the HRT had a MM 0.75 (IC 95% 0.62-1.15) p=0.28, the maternal nursing with MM 0.68 (IC 95% 0.59-1.08) p=0.05, the multiparity with MM 0.42 (IC 95% 0.16-1.87) p=0.26, obesity MM 1.67 (IC 95% 0.99-1.54) p=0.05, familial history with MM 1.23 (IC 95% 0.83-1.54) p=0.05.
  
  
  CONCLUSIONS
  These results show that does not exist a direct association between HRT and breast cancer. Therefore, whenever takes the decision to use the HRT should be considered the possible risks and benefits individualizing the patient, also the mammography should be present in mind, same that frequent physical examination, autoexploration and the use of HRT smaller to 5 years.
authors.affiliation: Hospital de Ginecología y Obstetricia número 3, Centro Médico Nacional La Raza y Unidad de Investigación Médica en Enfermedades Endocrinas, Centro Médico Nacional Siglo XXI, IMSS, México, DF.
authors.forename: María Antonia
authors.initials: MA
authors.lastname: Basavilvazo Rodríguez
authors.forename: Alfonso
authors.initials: A
authors.lastname: Díaz Quiroz
authors.forename: Roberto
authors.initials: R
authors.lastname: Lemus Rocha
authors.forename: Leobardo
authors.initials: L
authors.lastname: Angeles Victoria
authors.forename: Arturo
authors.initials: A
authors.lastname: Zárate
authors.forename: Marcelino
authors.initials: M
authors.lastname: Hernández-Valencia
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000139:chemically induced* / Q000453:epidemiology; D016022:Case-Control Studies; D015914:Estrogen Replacement Therapy / Q000009:adverse effects* / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008327:Mammography; D008875:Middle Aged; D012307:Risk Factors