Guideline Concordant Therapy Prolongs Survival in HER2-Positive Breast Cancer Patients : Results from a Large Population-Based Cohort of a Cancer Registry

Abstract EN

Even though randomized controlled clinical trials demonstrated improved survival by adjuvant trastuzumab treatment of HER2-positive breast cancer patients, data on its effect in clinical routine are scarce.

This study evaluated the use and efficacy of trastuzumab in routine treatment of HER2-positive breast cancer patients.

Data from the clinical cancer registry Regensburg (Germany) were analyzed.

The present study investigated 6,991 female patients with primary invasive breast cancer.

In premenopausal HER2-positive patients a considerable increase of trastuzumab therapy was observed from 58.1% in 2006 to 90.9% in 2011, whereas in postmenopausal patients trastuzumab was rather used on a constant rate of 49.1%.

Best overall survival (OS) was found in HER2/steroid hormone receptor-positive patients receiving guideline concordant treatment with trastuzumab plus chemotherapy (CHT) plus antihormone therapy (AHT) with a 7-year OS rate of 96% compared to the non-trastuzumab group with a 7-year OS rate of 92%.

In multivariable analysis, HER2-positive patients treated with CHT or AHT who did not get trastuzumab, had a worse 7-year OS (65%, P=0.006 versus 79%, P=0.017) than the control groups.

This population-based study demonstrated that guideline concordant use of adjuvant trastuzumab improves OS for HER2-positive breast cancer patients treated in routine clinical care.