Association between mammographic density and basal-like and luminal A breast cancer subtypes

Details

• Alternative Title:
  Breast Cancer Res
• Personal Author:
  Razzaghi, Hilda ; Troester, Melissa A ; Gierach, Gretchen L ; Olshan, Andrew F ; Yankaskas, Bonnie C ; Millikan, Robert C
• Description:
  Introduction
  
  Mammographic density is a strong risk factor for breast cancer overall, but few studies have examined the association between mammographic density and specific subtypes of breast cancer, especially aggressive basal-like breast cancers. Because basal-like breast cancers are less frequently screen-detected, it is important to understand how mammographic density relates to risk of basal-like breast cancer.
  
  Methods
  
  We estimated associations between mammographic density and breast cancer risk according to breast cancer subtype. Cases and controls were participants in the Carolina Breast Cancer Study (CBCS) who also had mammograms recorded in the Carolina Mammography Registry (CMR). A total of 491 cases had mammograms within five years prior to and one year after diagnosis and 528 controls had screening or diagnostic mammograms close to the dates of selection into CBCS. Mammographic density was reported to the CMR using Breast Imaging Reporting and Data System categories. The expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 1 and 2 (HER1 and HER2), and cytokeratin 5/6 (CK5/6) were assessed by immunohistochemistry and dichotomized as positive or negative, with ER+ and/or PR+, and HER2- tumors classified as luminal A and ER-, PR-, HER2-, HER1+ and/or CK5/6+ tumors classified as basal-like breast cancer. Triple negative tumors were defined as negative for ER, PR and HER2. Of the 491 cases 175 were missing information on subtypes; the remaining cases included 181 luminal A, 17 luminal B, 48 basal-like, 29 ER-/PR-/HER2+, and 41 unclassified subtypes. Odds ratios comparing each subtype to all controls and case-case odds ratios comparing mammographic density distributions in basal-like to luminal A breast cancers were estimated using logistic regression.
  
  Results
  
  Mammographic density was associated with increased risk of both luminal A and basal-like breast cancers, although estimates were imprecise. The magnitude of the odds ratio associated with mammographic density was not substantially different between basal-like and luminal A cancers in case–control analyses and case-case analyses (case-case OR = 1.08 (95% confidence interval: 0.30, 3.84)).
  
  Conclusions
  
  These results suggest that risk estimates associated with mammographic density are not distinct for separate breast cancer subtypes (basal-like/triple negative vs. luminal A breast cancers). Studies with a larger number of basal-like breast cancers are needed to confirm our findings.
  
  
• Subjects:
  Adult Aged Breast Neoplasms Case-Control Studies Female Humans Immunohistochemistry Mammary Glands, Human Middle Aged Neoplasms, Basal Cell Odds Ratio Receptor, ErbB-2 Receptors, Estrogen Receptors, Progesterone Registries Risk Tumor Markers, Biological

  More +
• Source:
  Breast Cancer Res. 2013; 15(5):R76.
• Document Type:
  Journal Article
• Funding:
  5P50CA058233/CA/NCI NIH HHS/United States ; 5R01CA138255/CA/NCI NIH HHS/United States ; 5U01ES019472-02/ES/NIEHS NIH HHS/United States ; P30 CA016086/CA/NCI NIH HHS/United States ; P30 ES010126/ES/NIEHS NIH HHS/United States ; P50 CA058223/CA/NCI NIH HHS/United States
• Volume:
  15
• Issue:
  5
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha256:124d4cd295e6f0ce8cd6ff89cb795f74b98bde19bbed04ccbe2b53d468792ae5
• Download URL:
  https://stacks.cdc.gov/view/cdc/29441/cdc_29441_DS1.pdf
• File Type:
  [PDF - 258.32 KB ]