Intrinsic subtypes, PIK3CA mutation, and the degree of benefit from adjuvant trastuzumab in the NSABP B-31 trial.

ABSTRACT:

Purpose

Considerable molecular heterogeneity exists among human epidermal growth factor receptor 2 (HER2) -positive breast cancer regarding gene expression and mutation profiling. Evidence from preclinical, clinical neoadjuvant, and metastatic clinical trials suggested that PIK3CA mutational status and PAM50 intrinsic subtype of a tumor were markers of response to anti-HER2 therapies. We evaluated the predictive value of these two biomarkers in the adjuvant setting using archived tumor blocks from National Surgical Adjuvant Breast and Bowel Project (NSABP) trial B-31.

Patients and methods

Expression data for 49 genes using the nCounter platform were used to generate PAM50 intrinsic subtypes for 1,578 archived tumor blocks from patients in the B-31 trial. Six PIK3CA hotspot m

SUBMITTER: Pogue-Geile KL 

PROVIDER: S-EPMC4397278 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature