[Internal quality control on HER2 status determination in breast cancers: Experience of a cancer center].

Introduction: The implementation of an internal quality control is mandatory to guarantee the accuracy of HER2 status in invasive breast cancers.

Objectives: To evaluate the impact of our quality control assurance on HER2 status results in invasive breast carcinomas from 2008 to 2014.

Methods: HER2 status was determined by immunohistochemistry as the first-line indication, completed by fluorescence in situ hybridization (FISH) for scores 2+ by immunohistochemistry.