Abstract

Despite >10 years of routine human epidermal growth factor receptor 2 (HER2) testing in breast cancer, testing quality is still an issue. Guidelines recommend assessing HER2 positivity rates as a quality indicator; however, the extent to which patient- or tumor-related factors influence HER2 positivity is still unknown. The present study analyzed these influences to identify pathology centers with HER2 positivity rates unexplained by patient- or tumor-related factors. This observational, prospective study monitored routine HER2 testing at 57 institutes of pathology in Germany (January 2013–August 2014). Data collected included HER2 test result, patient- and tumor-related factors, sample source, and method of sample retrieval. Factors influencing HER2 positivity rates were identified by multiple logistic regression. Individual center effects were assessed in an extended multiple logistic regression model by their statistical significance after adjusting for the combined effect of patient- or tumor-related covariates and multiple testing. Analyses included 15 332 invasive breast cancer samples. Histologic grade showed the strongest influence on HER2 positivity, followed by hormone receptor status, histologic subtype, age, and nodal status (all P<0.0001). The overall HER2 positivity rate across centers was 14.4% (range 7.1–27.3%). A statistically significant center effect on the HER2 positivity rate was identified for three centers (P<0.05), with a trend toward a center effect for a further three (P<0.2). This study, the first of its kind, highlights that assessing HER2 testing quality with HER2 positivity rates should include standardized assessment of patient- or tumor-related characteristics to identify centers with HER2 testing quality issues more effectively. As treatment options for HER2-positive breast cancer continue to evolve, identifying the right patients is key.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.