Breast cancer index identifies early-stage estrogen receptor-positive breast cancer patients at risk for early- and late-distant recurrence

Clin Cancer Res. 2013 Aug 1;19(15):4196-205. doi: 10.1158/1078-0432.CCR-13-0804. Epub 2013 Jun 11.

Abstract

Purpose: Residual risk of relapse remains a substantial concern for patients with hormone receptor-positive breast cancer, with approximately half of all disease recurrences occurring after five years of adjuvant antiestrogen therapy.

Experimental design: The objective of this study was to examine the prognostic performance of an optimized model of Breast Cancer Index (BCI), an algorithmic gene expression-based signature, for prediction of early (0-5 years) and late (>5 years) risk of distant recurrence in patients with estrogen receptor-positive (ER(+)), lymph node-negative (LN(-)) tumors. The BCI model was validated by retrospective analyses of tumor samples from tamoxifen-treated patients from a randomized prospective trial (Stockholm TAM, n = 317) and a multi-institutional cohort (n = 358).

Results: Within the Stockholm TAM cohort, BCI risk groups stratified the majority (∼65%) of patients as low risk with less than 3% distant recurrence rate for 0 to 5 years and 5 to 10 years. In the multi-institutional cohort, which had larger tumors, 55% of patients were classified as BCI low risk with less than 5% distant recurrence rate for 0 to 5 years and 5 to 10 years. For both cohorts, continuous BCI was the most significant prognostic factor beyond standard clinicopathologic factors for 0 to 5 years and more than five years.

Conclusions: The prognostic sustainability of BCI to assess early- and late-distant recurrence risk at diagnosis has clinical use for decisions of chemotherapy at diagnosis and for decisions for extended adjuvant endocrine therapy beyond five years.

Publication types

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

MeSH terms

  • Adult
  • Antineoplastic Agents, Hormonal / administration & dosage
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / genetics
  • Breast Neoplasms / pathology*
  • Female
  • Humans
  • Middle Aged
  • Neoplasm Recurrence, Local / drug therapy
  • Neoplasm Recurrence, Local / genetics
  • Neoplasm Recurrence, Local / pathology*
  • Neoplasm Staging
  • Prognosis*
  • Prospective Studies
  • Randomized Controlled Trials as Topic
  • Receptors, Estrogen / genetics
  • Retrospective Studies
  • Survival Rate
  • Tamoxifen / administration & dosage*

Substances

  • Antineoplastic Agents, Hormonal
  • Receptors, Estrogen
  • Tamoxifen