Lack of either estrogen or progesterone receptor expression is associated with poor survival outcome among luminal A breast cancer subtype

Ann Surg Oncol. 2013 May;20(5):1505-13. doi: 10.1245/s10434-012-2772-x. Epub 2012 Nov 29.

Abstract

Background: This study was designed to evaluate the impact of lack of either estrogen receptor (ER) or progesterone receptor (PR) on characteristics and outcomes among luminal A breast cancer subtype treated with endocrine with or without chemotherapeutic agents.

Methods: The luminal A subtype was categorized into three subgroups: ER+/PR+, ER+/PR-, and ER-/PR+. All tumors were human epidermal growth factor receptor 2 (HER2) negative. Clinicopathological features and survival were analyzed using the Severance Hospital dataset (n = 1,180) and were validated by the nationwide Korean Breast Cancer Society (KBCS) registry (n = 9,916).

Results: Despite the different distribution of ER/PR status, tumor stage, grade, and local therapies between the two datasets, similarly ER+/PR+ showed smaller size and good differentiation, ER+/PR- patients had the oldest age at diagnosis, and ER-/PR+ was associated with the youngest age at onset and grade III tumor. Single hormone receptor-positive subgroups demonstrated worse disease-related outcomes than the ER+/PR+ subgroup. These associations were confirmed by the KBCS dataset. This trend was also demonstrated in the subpopulation of 1,944 patients with Ki-67 < 14 %. Inferior survival of single receptor-positive tumors was more definite among node-positive patients even when receiving both chemo-endocrine therapies.

Conclusions: Current results suggest that the luminal A subtype is also heterogeneous and each subgroup has unique clinicopathologic characteristics. Lack of either ER or PR expression is associated with worse survival, especially among node-positive luminal A subtype.

MeSH terms

  • Adult
  • Age Factors
  • Breast Neoplasms / metabolism*
  • Breast Neoplasms / pathology*
  • Breast Neoplasms / therapy
  • Chemotherapy, Adjuvant
  • Disease-Free Survival
  • Female
  • Humans
  • Kaplan-Meier Estimate
  • Ki-67 Antigen / metabolism
  • Middle Aged
  • Neoplasm Grading
  • Neoplasm Metastasis
  • Proportional Hazards Models
  • Receptor, ErbB-2 / metabolism
  • Receptors, Estrogen / metabolism*
  • Receptors, Progesterone / metabolism*
  • Registries
  • Republic of Korea

Substances

  • Ki-67 Antigen
  • Receptors, Estrogen
  • Receptors, Progesterone
  • ERBB2 protein, human
  • Receptor, ErbB-2