Breast cancer heterogeneity – report from IMPAKT Breast Cancer Conference Review article

Abstract

On 2–4 May 2013, in Brussels took place the 5th IMPAKT conference on translational research in breast cancer. The most important issue raised during the conference was the phenomenon of breast cancer heterogeneity, both inter- and intratumour. Heterogeneity of breast cancer was confirmed at the molecular level, showing the differences in the frequency of genetic aberrations (typically PIK3CA, TP53 and ARID1A) in patients with hormone-dependent advanced breast cancer (BOLERO-2 trial). The results of genetic tests were also presented, which showed that in order to reduce the impact of heterogeneity within the tumor, 3 biopsies should be performed from each breast cancer. The most common disorders of PI3K/mTOR pathway were analyzed depending on the molecular type of breast cancer. However, an attempt to determine by immunohistochemistry biomarkers predicting response to combination therapy with everolimus and trastuzumab failed. The results of two studies, which analyzed the value of molecular tests in predicting late recurrence of breast cancer (in 5–10 years after diagnosis), were presented – the best results were achieved with PAM50 and Breast Cancer Index. The latest discoveries in molecular imaging were also presented – it allows for early assessment of treatment efficacy.