Reproductive risk factor associations with lobular and ductal carcinoma in the Carolina Breast Cancer Study.

Journal Article (Journal Article)

BACKGROUND: Invasive lobular breast tumors display unique reproductive risk factor profiles. Lobular tumors are predominantly Luminal A subtype, and it is unclear whether reported risk factor associations are independent of molecular subtype. METHODS: Polytomous logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) for the associations between risk factors and histologic subtype [ductal (n = 2,856), lobular (n = 326), and mixed ductal-lobular (n = 473)] in the Carolina Breast Cancer Study (1993-2013). Three-marker immunohistochemical clinical subtypes were defined as Luminal A (ER+ or PR+/HER2-), Luminal B (ER+ or PR+/HER2+), Triple Negative (ER-/PR-/HER2-), and HER2+ (ER-/PR-/HER2+). RESULTS: In case-case analyses compared to ductal, lobular tumors were significantly associated with lactation duration > 12 months [OR 1.86, 95% CI (1.33-2.60)], age at first birth ≥ 26 years [OR: 1.35, 95% CI: (1.03-1.78)], and current oral contraceptive use [OR: 1.86, 95% CI: (1.08-3.20)]. Differences in risk factor associations between ductal and lobular tumors persisted after restricting to Luminal A subtype. CONCLUSIONS: Lobular tumors were associated with older age at first birth, increased lactation duration, and current oral contraceptive use. Etiologic heterogeneity by histology persisted after restricting to Luminal A subtype, suggesting both tumor histology and intrinsic subtype play integral parts in breast cancer risk.

Full Text

Duke Authors

Cited Authors

  • Williams, LA; Nichols, HB; Hoadley, KA; Tse, CK; Geradts, J; Bell, ME; Perou, CM; Love, MI; Olshan, AF; Troester, MA

Published Date

  • January 2018

Published In

Volume / Issue

  • 29 / 1

Start / End Page

  • 25 - 32

PubMed ID

  • 29124544

Pubmed Central ID

  • PMC5903274

Electronic International Standard Serial Number (EISSN)

  • 1573-7225

Digital Object Identifier (DOI)

  • 10.1007/s10552-017-0977-9


  • eng

Conference Location

  • Netherlands