title: Risk of subsequent breast cancer in relation to characteristics of screening mammograms from women less than 50 years of age.
abstract: This investigation was conducted to assess the predictive value of calcifications and densities in mammograms from women <50 years of age for subsequent diagnosis of breast cancer. In a population-based study, prior screening mammograms taken before age 50 in 547 women with breast cancer and 472 controls were reviewed by a single radiologist. The relative risk (RR) of subsequent breast cancer increased with the percentage of the area of the mammogram that was mammographically dense [RR in succeeding quartiles of density = 1.0, 1.7 (1.1-2.6), 3.3 (2.2-5.0), and 4.0 (2.7-6.0)]; in relation to Wolfe parenchymal pattern class P2 [RR = 3.1 (2.2-4.3)] or DY [RR = 5.6 (3.2-10.0)]; and in relation to calcifications of class 1 (pleomorphic of any distribution) or class 2 (various morphological types that are regional, grouped, clustered, segmental, or linear in distribution) [RR = 3.0 (1.4-7.1), and 1.8 (1.2-2.6), respectively]. Women with radiographically dense mammograms and class 1 or 2 calcifications were at >10- and approximately 6-fold greater risk, respectively, than women with breasts of low density and no calcifications. Densities and parenchymal patterns were most strongly associated with breast cancer being diagnosed in the next 3 years. Class 1 and 2 calcifications were most strongly predictive of an increased risk in 3-6 years. Class 1 calcifications were strongly predictive of the breast in which the subsequent cancer occurred. Women <50 years of age with class 1 or 2 calcifications or mammographically dense breasts, or both, should receive high priority for further evaluation and regular breast cancer screening.
authors.affiliation: Program in Epidemiology, The Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024, USA. dbthomas@fhcrc.org
authors.forename: David B
authors.initials: DB
authors.lastname: Thomas
authors.forename: Rachel A
authors.initials: RA
authors.lastname: Carter
authors.forename: William H
authors.initials: WH
authors.lastname: Bush
authors.forename: Roberta M
authors.initials: RM
authors.lastname: Ray
authors.forename: Janet L
authors.initials: JL
authors.lastname: Stanford
authors.forename: Constance D
authors.initials: CD
authors.lastname: Lehman
authors.forename: Janet R
authors.initials: JR
authors.lastname: Daling
authors.forename: Kathi
authors.initials: K
authors.lastname: Malone
authors.forename: Scott
authors.initials: S
authors.lastname: Davis
mesh_terms: D000328:Adult; D000367:Age Factors; D001941:Breast Diseases / Q000473:pathology*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000209:etiology; D002114:Calcinosis; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008327:Mammography; D008403:Mass Screening; D008875:Middle Aged; D011237:Predictive Value of Tests; D018570:Risk Assessment