Development in incidence of breast cancer in non-screened Danish women, 1973-2002--a population-based study.
The authors report on the incidence rates of breast cancer overall and by histology in a population of unscreened women constituting approximately 80% of the total population of women in Denmark from 1973-2002, utilizing the files of the nationwide Danish Cancer Registry. The age-specific incidence rates of breast cancer increased throughout the period, and further, marked changes in the age-specific incidence pattern were observed, where the plateau and change of slope around the age of 46-48 in 1973-1981 shifted to around age 64-66 years in 1994-2002. Age-period-cohort modeling indicated that these changes were not attributable to a birth cohort effect. Although lobular breast cancer incidence increased more than ductal breast cancer incidence, this was only observed in the first decade after the introduction of the ICD-O system in Denmark and probably is attributable to this, whereas we observed no disproportionate changes by histology in any age group from 1988-2002. Thus, previous reports of a disproportionate increase in lobular breast cancer could not be confirmed in a non-screened population, whereas important changes over the past decade in the age-specific incidence pattern of breast cancer particular around the time of menopause were indicated.
Fuglede
Niels
N
Institute of Cancer Epidemiology, Danish Cancer Society, Copenhagen, Denmark.
Langballe
Oline
O
Svendsen
Anne Louise
AL
Tjønneland
Anne
A
Dalton
Susanne O
SO
Johansen
Christoffer
C
D000367:Age Factors; D000368:Aged; D001943:Breast Neoplasms / Q000453:epidemiology*; D018270:Carcinoma, Ductal, Breast / Q000453:epidemiology*; D018275:Carcinoma, Lobular / Q000453:epidemiology*; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D008403:Mass Screening; D008593:Menopause; D008875:Middle Aged; D012042:Registries / Q000706:statistics & numerical data*