Incidence and Survival by Human Epidermal Growth Factor Receptor 2 Status in Young Women With Stage I-III Breast Cancer: SEER, 2010-2016

Clin Breast Cancer. 2020 Aug;20(4):e410-e422. doi: 10.1016/j.clbc.2020.01.014. Epub 2020 Feb 4.

Abstract

Background: Young premenopausal women with breast cancer often experience more aggressive disease biology and poorer survival than older women. Diagnostic and therapeutic advances, including human epidermal growth factor receptor 2 (HER2)-directed therapy, may lessen treatment burden and improve survival for these young women, but contemporary incidence and survival data by HER2 status are limited.

Patients and methods: We identified women aged 20-49 years (n = 68,530) diagnosed with stage I-III breast cancer during 2010-2016 from the United States Surveillance, Epidemiology, and End Results 18 registries database. Age-adjusted average annual percent changes in incidence (diagnosis 2010-2016) and 5-year Kaplan-Meier survival curves (diagnosis 2010-2015) were estimated by HER2 and hormone receptor (HR) status and stratified independently by cancer stage and race/ethnicity.

Results: With increasing age decade, proportions of HER2-/HR+ cancer increased, whereas proportions of HER2+/HR+, HER2+/HR-, and HER2-/HR- decreased. The greatest increases in incidence during 2010-2016 were observed for HER2+ among women aged 20-49 years and HER2-/HR- among women aged 20-29 years. Incidence decreased for HER2-/HR- among women aged 40-49 years. Five-year survival was lowest for HER2-/HR- status compared to other receptor-based subtypes among women aged 20-49 years. HER2+ status was more beneficial for 5-year survival than HR+ status among women aged 20-29 years, with the opposite observed among women aged 30-49 years, particularly those aged 40-49 years.

Conclusion: HER2+ breast cancer increased among premenopausal women and was also associated with higher early survival within each HR status. HER2-/HR- cancer also increased among women aged 20-29 years and was associated with lower early survival. Our contemporary data provide important insights to help inform preventive and therapeutic strategies for premenopausal women.

Keywords: Breast neoplasms; Incidence study; Neoplasm staging; Registries; Survival analysis.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Biomarkers, Tumor / analysis
  • Biomarkers, Tumor / metabolism*
  • Breast / pathology*
  • Breast Neoplasms / diagnosis
  • Breast Neoplasms / epidemiology*
  • Breast Neoplasms / pathology
  • Female
  • Humans
  • Incidence
  • Kaplan-Meier Estimate
  • Middle Aged
  • Neoplasm Staging
  • Premenopause
  • Prognosis
  • Receptor, ErbB-2 / analysis
  • Receptor, ErbB-2 / metabolism*
  • Receptors, Estrogen / analysis
  • Receptors, Estrogen / metabolism
  • Receptors, Progesterone / analysis
  • Receptors, Progesterone / metabolism
  • Retrospective Studies
  • SEER Program / statistics & numerical data
  • United States / epidemiology
  • Young Adult

Substances

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