title: [Breast cancer in replacement therapy users under Mainero's classification].
abstract: BACKGROUND
  Breast cancer incidence associated with hormonal replacement therapy have been evaluated in many studies, which have found a hard to proof increment due to several particular patient factors.
  
  
  OBJECTIVE
  Many studies have been assessed the incidence of breast cancer in relation to the use of replacement therapy, however it is difficult to prove absolutely, every women has a different risk, influenced by genetic factors, nuliparity, late parity, menarche, menopause, use of estrogens, mastographic density and previous mammary disease.
  
  
  OBJECTIVE
  To identify if there is an increase in the number of cases of breast cancer in postmenopausal women with replacement therapy, with low and medium level in Mainero's classification.
  
  
  METHODS
  Cohort study prospective, and closed in 316 women with a 0, 1 or 2 result according to the Mainero's classification. 25 were excluded, 74 with a score of 0, 193 score of 1 and 24 score of 2, we followed all the women for 60 to 90 months with replacement therapy.
  
  
  RESULTS
  We did not find patients with breast cancer and replacement therapy.
  
  
  CONCLUSIONS
  Mainero's classification is an easy option to evaluate and decide replacement therapy taking the oncology risk.
authors.affiliation: Unidad Médica de Alta Especialidad Luis Castelazo Ayala, Instituto Mexicano del Seguro Social, México, DF. jennyfragoso@yahoo.com
authors.forename: Jeniffer
authors.initials: J
authors.lastname: Fragoso Dávila
authors.forename: Fernando
authors.initials: F
authors.lastname: Mainero Ratchelous
mesh_terms: D001943:Breast Neoplasms / Q000453:epidemiology*; D005260:Female; D020249:Hormone Replacement Therapy / Q000145:classification; D006801:Humans; D008875:Middle Aged; D011446:Prospective Studies