US incidence of breast cancer subtypes defined by joint hormone receptor and HER2 status

J Natl Cancer Inst. 2014 Apr 28;106(5):dju055. doi: 10.1093/jnci/dju055.

Abstract

Background: In 2010, Surveillance, Epidemiology, and End Results (SEER) registries began collecting human epidermal growth factor 2 (HER2) receptor status for breast cancer cases.

Methods: Breast cancer subtypes defined by joint hormone receptor (HR; estrogen receptor [ER] and progesterone receptor [PR]) and HER2 status were assessed across the 28% of the US population that is covered by SEER registries. Age-specific incidence rates by subtype were calculated for non-Hispanic (NH) white, NH black, NH Asian Pacific Islander (API), and Hispanic women. Joint HR/HER2 status distributions by age, race/ethnicity, county-level poverty, registry, stage, Bloom-Richardson grade, tumor size, and nodal status were evaluated using multivariable adjusted polytomous logistic regression. All statistical tests were two-sided.

Results: Among case patients with known HR/HER2 status, 36810 (72.7%) were found to be HR(+)/HER2(-), 6193 (12.2%) were triple-negative (HR(-)/HER2(-)), 5240 (10.3%) were HR(+)/HER2(+), and 2328 (4.6%) were HR(-)/HER2(+); 6912 (12%) had unknown HR/HER2 status. NH white women had the highest incidence rate of the HR(+)/HER2(-) subtype, and NH black women had the highest rate of the triple-negative subtype. Compared with women with the HR(+)/HER2(-) subtype, triple-negative patients were more likely to be NH black and Hispanic; HR(+)/HER2(+) patients were more likely to be NH API; and HR(-)/HER2(+) patients were more likely to be NH black, NH API, and Hispanic. Patients with triple-negative, HR(+)/HER2(+), and HR(-)/HER2(+) breast cancer were 10% to 30% less likely to be diagnosed at older ages compared with HR(+)/HER2(-) patients and 6.4-fold to 20.0-fold more likely to present with high-grade disease.

Conclusions: In the future, SEER data can be used to monitor clinical outcomes in women diagnosed with different molecular subtypes of breast cancer for a large portion (approximately 28%) of the US population.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • African Continental Ancestry Group
  • Aged
  • Breast Neoplasms / classification*
  • Breast Neoplasms / epidemiology*
  • Breast Neoplasms / ethnology
  • Breast Neoplasms / metabolism
  • European Continental Ancestry Group
  • Female
  • Humans
  • Incidence
  • Middle Aged
  • Receptor, ErbB-2 / biosynthesis*
  • Receptors, Estrogen / biosynthesis*
  • Receptors, Progesterone / biosynthesis*
  • Registries
  • SEER Program
  • Triple Negative Breast Neoplasms / classification*
  • Triple Negative Breast Neoplasms / epidemiology*
  • Triple Negative Breast Neoplasms / ethnology
  • Triple Negative Breast Neoplasms / metabolism
  • United States / epidemiology

Substances

  • Receptors, Estrogen
  • Receptors, Progesterone
  • ERBB2 protein, human
  • Receptor, ErbB-2