Prognostic and predictive value of tumor vascular endothelial growth factor gene amplification in metastatic breast cancer treated with paclitaxel with and without bevacizumab; results from ECOG 2100 trial

Clin Cancer Res. 2013 Mar 1;19(5):1281-9. doi: 10.1158/1078-0432.CCR-12-3029. Epub 2013 Jan 22.

Abstract

Purpose: Clinically validated biomarkers for anti-angiogenesis agents are not available. We have previously reported associations between candidate VEGFA single-nucleotide polymorphisms (SNP) and overall survival (OS) in E2100. The associations between tumor VEGFA amplification and outcome are evaluated here.

Experimental design: E2100 was a phase III trial comparing paclitaxel with or without bevacizumab for patients with metastatic breast cancer. FISH to assess gene amplification status for VEGFA was conducted on paraffin-embedded tumors from 363 patients in E2100. Evaluation for association between amplification status and outcomes was conducted.

Results: Estrogen receptor (ER)+ or progesterone receptor (PR)+ tumors were less likely to have VEGFA amplification than ER/PR- tumors (P = 0.020). VEGFA amplification was associated with worse OS (20.2 vs. 25.3 months; P = 0.013) in univariate analysis with a trend for worse OS in multivariate analysis (P = 0.08). There was a significant interaction between VEGFA amplification, hormone receptor status, and study arm. Patients with VEGFA amplification and triple-negative breast cancers (TNBC) or HER2 amplification had inferior OS (P = 0.047); amplification did not affect OS for those who were ER+ or PR+ and HER2-. Those who received bevacizumab with VEGFA amplification had inferior progression-free survival (PFS; P = 0.010) and OS (P = 0.042); no association was seen in the control arm. Test for interaction between study arm and VEGFA amplification with OS was not significant.

Conclusion: VEGFA amplification in univariate analysis was associated with poor outcomes; this was particularly prominent in HER2+ or TNBCs. Additional studies are necessary to confirm the trend for poor OS seen on multivariate analysis for patients treated with bevacizumab.

Publication types

  • Clinical Trial, Phase III
  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antibodies, Monoclonal, Humanized / administration & dosage
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use*
  • Bevacizumab
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / genetics
  • Breast Neoplasms / mortality
  • Female
  • Follow-Up Studies
  • Gene Amplification*
  • Humans
  • In Situ Hybridization, Fluorescence
  • Middle Aged
  • Neoplasm Metastasis
  • Neoplasm Staging
  • Paclitaxel / administration & dosage
  • Prognosis
  • Receptor, ErbB-2 / metabolism
  • Receptors, Estrogen / metabolism
  • Receptors, Progesterone / metabolism
  • Retrospective Studies
  • Survival Rate
  • Tissue Array Analysis
  • Vascular Endothelial Growth Factor A / genetics*

Substances

  • Antibodies, Monoclonal, Humanized
  • Receptors, Estrogen
  • Receptors, Progesterone
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A
  • Bevacizumab
  • Receptor, ErbB-2
  • Paclitaxel