Multigene assays and isolated tumor cells for early breast cancer treatment: time for bionetworks

Abstract

Despite advances with adjuvant endocrine treatment for hormone receptor-positive tumors and with trastuzumab for HER2-positive disease, overall, over 50% of women with early-stage breast cancer experience recurrence and die of the disease. Biomarkers for tailoring systemic adjuvant treatment to responder patients are needed. The multigene assays, 21-gene recurrence score (Oncotype DX^® [Genomic Health, CA, USA]) and 70-gene signature (MammaPrint™ [Agendia, CA, USA]), and the isolated tumor cells in sentinel lymph node(s) represent the latest advances for improving adjuvant chemotherapy decisions. This article evaluates how these new markers, added to current standard factors (age, tumor size, grade, hormone receptor status and HER2 status), could improve early breast cancer treatment decisions. Moreover, emerging evidence from the latest large-scale studies using next-generation DNA-sequencing technology reveals a high heterogeneity and complexity of breast cancer. This assessment now shapes a new research strategy towards completion of a breast cancer causal (driver) mutations catalog and understanding complex genetic interactions and signaling pathway networks. Despite multiple challenges, advances in cancer genomes and systems biology approaches promise the future development of robust biomarkers.

Keywords::

• breast cancer
• cancer genomes
• multigene assays
• node negative
• systems biology

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.