Table 4

RRs of breast cancer in relation to presence of each specific type of calcification in either breast on prior mammogram

Calcification classificationaNumber of subjectsRRb (95% CI)RRc (95% CI)
Cases (n = 547)Controls (n = 472)
No calcification1922291.0 (reference)1.0 (reference)
Nonepithelial, class 531330.7 (0.4–1.2)0.8 (0.5–1.4)
Epithelial, class 42281661.3 (1.0–1.7)1.3 (1.0–1.7)
Epithelial, class 3133871.2 (0.9–1.7)1.2 (0.8–1.6)
Epithelial, class 2111551.8 (1.3–2.6)1.8 (1.2–2.6)
Epithelial, class 13483.4 (1.6–8.0)3.0 (1.4–7.1)
  • a Includes pleomorphic morphology of any distribution (class 1); other morphological epithelial calcification of regional, grouped, clustered, segmental, or linear distribution (class 2); of diffuse or scattered distribution (class 3); or as single entities (class 4); and any nonepithelial type (class 5).

  • b Adjusted for age, study, and other class of calcifications present.

  • c Adjusted for age, study, other type of calcification and Wolfe class (three categories: N1 + P1, P2, and DY).