PIK3CA mutations are associated with decreased benefit to neoadjuvant human epidermal growth factor receptor 2-targeted therapies in breast cancer.

ABSTRACT:

Purpose

We investigated whether mutations in the gene encoding the phosphatidylinositol 3-kinase (PI3K) catalytic subunit (PIK3CA) correlates with response to neoadjuvant human epidermal growth factor receptor 2 (HER2) -targeted therapies in patients with breast cancer.

Patients and methods

Baseline tissue biopsies were available from patients with HER2-positive early breast cancer who were enrolled onto the Neoadjuvant Lapatinib and/or Trastuzumab Treatment Optimization trial (NeoALTTO). Activating mutations in PIK3CA were identified using mass spectrometry-based genotyping.

Results

PIK3CA mutations were identified in 23% of HER2-positive breast tumors, and these mutations were associated with poorer outcome in all of the treatment arms. Patients treated with a combi

SUBMITTER: Majewski IJ 

PROVIDER: S-EPMC5087318 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature