title: Past Trends and Future Estimation of Annual Breast Cancer Incidence in Osaka, Japan.
abstract: BACKGROUND
  Although the breast cancer incidence rate in Japan is lower than in western countries, the age-specific rates have markedly increased in recent years, along with the problems of declining birth rate and an aging population.
  
  
  METHODS
  We examined past trends of age-specific breast cancer incidence using data from the Osaka Cancer Registry from 1976 to 2010, and estimated future trends until 2025 based on the changes observed and population dynamics using a log linear regression model.
  
  
  RESULTS
  The age-specific breast cancer incidence rate has increased consistently from the 1970s, and the rates have caught up with those of Japanese-Americans in the US. Assuming the increasing tendency of age-specific breast cancer incidence to be constant, the average annual incidence of breast cancer will increase 1.7-fold from 2006-2010 to 2021-2025. Furthermore, the number of patients aged 80 years should increase 3.4-fold.
  
  
  CONCLUSIONS
  The medical demand for breast cancer care in Japan may increase explosively in the future, particularly among the elderly. We need to prepare for such a future increase in demand for care, although careful monitoring is needed to confirm these results.
authors.affiliation: Department of Surgery, Saiseikai Senri Hospital, Suita-shi, Osaka, Japan E-mail : ytoyoda@osaka.med.or.jp.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Toyoda
authors.forename: Takahiro
authors.initials: T
authors.lastname: Tabuchi
authors.forename: Tomio
authors.initials: T
authors.lastname: Nakayama
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Hojo
authors.forename: Setsuko
authors.initials: S
authors.lastname: Yoshioka
authors.forename: Yoshiichi
authors.initials: Y
authors.lastname: Maeura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008875:Middle Aged; D009367:Neoplasm Staging; D011158:Population Growth; D011379:Prognosis; D012042:Registries / Q000706:statistics & numerical data*; D013997:Time Factors; D055815:Young Adult