title: The effect of age and density of the breast on the sensitivity of breast cancer diagnostic by mammography and ultasonography.
abstract: OBJECTIVE
  We studied which, age of the patient or density of the breast accounts for the sensitivity of mammography and ultrasonography (US). Furthermore we studied whether the overall impression on the density of the breast or the density in tumour area accounts for the sensitivity of mammography and ultrasonography.
  
  
  METHODS
  The material consisted of 572 consecutive histologically and 5 cytologically verified breast cancer cases. Mammography and US examinations were performed immediately before breast cancer operations and information on the findings were received from the original patient files and classified as malignant or benign. The density of breast parenchyma to fatty, mixed or dense in total breast and separately in tumour area was defined by a radiologist group from the original mammograms by comparing to model mammograms. The sensitivity (Se) of mammography and US was compared in 3 age groups (26-49, 50-59 and 60-92) and in the different density classes.
  
  
  RESULTS
  Sensitivity of mammography increased by age (density-adjusted OR = 0.2, 95%, CI 0.1-0.5) in age group 26-49 compared to age group 60-92) and with fattiness of the breast (age-adjusted OR= 0.4, 95%, CI 0.1-1.0 for dense breast parenchyma in tumour area compared to fatty breast). Sensitivity of US was inversely related to age (density-adjusted OR = 2.3, 95%, CI 1.0-5.2 in age group 26-49 compared to age group 60-92) and directly related with fattiness of breast (age-adjusted OR = 0.5, 95%, CI 0.2-0.9 by dense breast parenchyma in tumour area compared to fatty breast). Density in the tumour area compared to total breast density was related only mariginally better sensitivity both of mammography (0.4 vs. 0.6) and of US (0.5 vs. 0.6).
  
  
  CONCLUSIONS
  Sensitivity of both mammography and sensitivity of US are independently related both to the age of the patient and to the density of the breast. The effect of age is inverse and that of density parallel between mammography and US on sensitivity. The effect of overall breast density was close to the effect of density at the site of the tumour on the sensitivity of both mammography and US.
authors.affiliation: Pirkanmaa Cancer Society, Tampere, Finland.
authors.forename: I
authors.initials: I
authors.lastname: Saarenmaa
authors.forename: T
authors.initials: T
authors.lastname: Salminen
authors.forename: U
authors.initials: U
authors.lastname: Geiger
authors.forename: P
authors.initials: P
authors.lastname: Heikkinen
authors.forename: S
authors.initials: S
authors.lastname: Hyvärinen
authors.forename: J
authors.initials: J
authors.lastname: Isola
authors.forename: V
authors.initials: V
authors.lastname: Kataja
authors.forename: M L
authors.initials: ML
authors.lastname: Kokko
authors.forename: R
authors.initials: R
authors.lastname: Kokko
authors.forename: E
authors.initials: E
authors.lastname: Kumpulainen
authors.forename: A
authors.initials: A
authors.lastname: Kärkkäinen
authors.forename: J
authors.initials: J
authors.lastname: Pakkanen
authors.forename: P
authors.initials: P
authors.lastname: Peltonen
authors.forename: A
authors.initials: A
authors.lastname: Piironen
authors.forename: A
authors.initials: A
authors.lastname: Salo
authors.forename: M L
authors.initials: ML
authors.lastname: Talviala
authors.forename: M
authors.initials: M
authors.lastname: Haka
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001940:Breast / Q000033:anatomy & histology*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008327:Mammography; D008875:Middle Aged; D012680:Sensitivity and Specificity; D014463:Ultrasonography