Dataset Information

PIK3CA mutation impact on survival in breast cancer patients and in ERα, PR and ERBB2-based subgroups.

ABSTRACT:

Introduction

PIK3CA is the oncogene showing the highest frequency of gain-of-function mutations in breast cancer, but the prognostic value of PIK3CA mutation status is controversial.

Methods

We investigated the prognostic significance of PIK3CA mutation status in a series of 452 patients with unilateral invasive primary breast cancer and known long-term outcome (median follow-up 10 years).

Results

PIK3CA mutations were identified in 151 tumors (33.4%). The frequency of PIK3CA mutations differed markedly according to hormone receptor (estrogen receptor alpha [ERα] and progesterone receptor [PR]) and ERBB2 status, ranging from 12.5% in the triple-negative subgroup (ER-/PR-/ERBB2-) to 41.1% in the HR+/ERBB2- subgroup. PIK3CA mutation was associated with significantly longer metastasis-free survival in the overall population (P = 0.0056), and especially in the PR-positive and ERBB2-positive subgroups. In Cox multivariate regression analysis, the prognostic significance of PIK3CA mutation status persisted only in the ERBB2-positive subgroup.

Conclusions

This study confirms the high prevalence of PIK3CA mutations in breast cancer. PIK3CA mutation is an emerging tumor marker which might become used in treatment-choosing process. The independent prognostic value of PIK3CA mutation status in ERBB2-positive breast cancer patients should be now confirmed in larger series of patients included in randomized prospective ERBB2-based clinical trials.

SUBMITTER: Cizkova M

PROVIDER: S-EPMC3496146 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature

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Publications

PIK3CA mutation impact on survival in breast cancer patients and in ERα, PR and ERBB2-based subgroups.

Cizkova Magdalena M Susini Aurélie A Vacher Sophie S Cizeron-Clairac Géraldine G Andrieu Catherine C Driouch Keltouma K Fourme Emmanuelle E Lidereau Rosette R Bièche Ivan I

Breast cancer research : BCR 20120213 1

<h4>Introduction</h4>PIK3CA is the oncogene showing the highest frequency of gain-of-function mutations in breast cancer, but the prognostic value of PIK3CA mutation status is controversial.<h4>Methods</h4>We investigated the prognostic significance of PIK3CA mutation status in a series of 452 patients with unilateral invasive primary breast cancer and known long-term outcome (median follow-up 10 years).<h4>Results</h4>PIK3CA mutations were identified in 151 tumors (33.4%). The frequency of PIK3 ...[more]

PMID: 22330809

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Dataset Information

PIK3CA mutation impact on survival in breast cancer patients and in ERα, PR and ERBB2-based subgroups.

Introduction

Methods

Results

Conclusions

Publications

PIK3CA mutation impact on survival in breast cancer patients and in ERα, PR and ERBB2-based subgroups.

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