title: Breast cancer following augmentation mammoplasty (United States).
abstract: OBJECTIVE
  Although clinical reports have raised concern that breast implants may either increase the risk of breast cancer or delay its diagnosis, epidemiologic studies have generally shown implant recipients to be at a reduced risk of subsequent breast cancer. A large retrospective cohort study was undertaken to clarify effects of cosmetic breast implantation.
  
  
  METHODS
  Medical records of 13,488 women receiving cosmetic implants at 18 plastic surgery practices and a group of 3936 patients who received other types of plastic surgery at the same practices were reviewed and information abstracted. Questionnaires were sent to all subjects located as alive, with 71% being completed. Attempts were made to obtain medical verification for all reported cancers and to obtain death certificates for deceased subjects.
  
  
  RESULTS
  A total of 136 breast cancers were observed among the breast implant patients. External analyses, using general population rates from the Surveillance, Epidemiology and End Results (SEER) program, resulted in 152.2 cases expected and a standardized incidence ratio (SIR) of 0.9 (95% CI 0.8-1.1). A comparable SIR was found for the other plastic surgery patients (SIR =1.0, 95% CI 0.7-1.2). Internal analyses, directly comparing the implant patients with the other plastic surgery patients, showed a RR of 0.8 (95% CI 0.6-1.1). In neither the external nor internal analyses was there any systematic variation in risk by age or calendar year of initial implant. Risk also did not vary by years of follow-up or by type of implant. Risk was not affected by exclusion of patients who received their implants following surgery for benign breast disease. Although breast tumors tended to be detected at a somewhat later stage among the breast implant than the comparison patients, the difference was not statistically significant, nor was there any significant difference in breast cancer mortality between the two groups.
  
  
  CONCLUSIONS
  Breast implants do not appear to alter the risk of subsequent breast cancer.
authors.affiliation: Epidemiology and Biostatistics Program, National Cancer Institute, Bethesda, MD, USA.
authors.forename: L A
authors.initials: LA
authors.lastname: Brinton
authors.forename: J H
authors.initials: JH
authors.lastname: Lubin
authors.forename: M C
authors.initials: MC
authors.lastname: Burich
authors.forename: T
authors.initials: T
authors.lastname: Colton
authors.forename: S L
authors.initials: SL
authors.lastname: Brown
authors.forename: R N
authors.initials: RN
authors.lastname: Hoover
mesh_terms: D000328:Adult; D000367:Age Factors; D018427:Breast Implants / Q000009:adverse effects*; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000473:pathology*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D016462:Mammaplasty / Q000401:mortality* / Q000706:statistics & numerical data*; D008875:Middle Aged; D011159:Population Surveillance; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment; D014481:United States