For many patients with advanced breast cancer

PIK3CA mutations have typically been associated with a poor prognosis1

~40% of patients with HR+ breast cancers harbor activating mutations in the PIK3CA isoform of PI3K—the most common mutation in HR+ breast cancer2-5

In HR+ breast cancer2,6

PIK3CA mutations are a key driver of breast cancer and have typically been associated with a poor prognosis1,7

The high prevalence and role of PIK3CA mutations in breast cancer have drawn increasing interest8

HER2=human epidermal growth factor receptor 2.


  1. Aleskandarany MA, Rakha EA, Ahmed MA, et al. PIK3CA expression in invasive breast cancer: a biomarker of poor prognosis. Breast Cancer Res Treat. 2010;122(1):45-53.
  2. Sabine VS, Crozier C, Brookes CL, et al. Mutational analysis of PI3K/AKT signaling pathway in Tamoxifen Exemestane Adjuvant Multinational pathology study. J Clin Oncol. 2014;32(27):2951-2958.
  3. Thorpe LM, Yuzugullu H, Zhao JJ. PI3K in cancer: divergent roles of isoforms, modes of activation and therapeutic targeting. Nat Rev Cancer. 2015;15(1):7-24.
  4. LoRusso PM. Inhibition of the PI3K/AKT/mTOR pathway in solid tumors. J Clin Oncol. 2016;34(31):3803-3815.
  5. The Cancer Genome Atlas Network. Comprehensive molecular portraits of human breast tumours. Nature. 2012;490(7418):61-70.
  6. Howlader N, Altekruse SF, Li CI, et al. US incidence of breast cancer subtypes defined by joint hormone receptor and HER2 status. J Natl Cancer Inst. 2014;106(5). doi: 10.1093/jnci/dju055.
  7. Zardavas D, Phillips WA, Loi S. PIK3CA mutations in breast cancer: reconciling findings from preclinical and clinical data. Breast Cancer Res. 2014;16(1):201.
  8. Al-Sukhun S, Lataifeh I, Al-Sukhun R. Defining the prognostic and predictive role of PIK3CA mutations: sifting through the conflicting data. Curr Breast Cancer Rep. 2016;8:73-79.