Pathologic diagnosis, immunohistochemistry, multigene assays and breast cancer treatment: progress toward “precision” cancer therapy

Abstract

Clinical decisions regarding the suitability of adjuvant systemic therapy for individual patients with breast cancer depends on comprehensive assessment of the underlying biology of each patient's tumor. The previous clinical-pathologic paradigm for treatment, which had been used for decades, now has been augmented by significant advances in molecular analysis of breast tumor tissue samples. Molecular testing has the potential to understand better both tumor biology and clinical behavior, which enables more appropriate therapy choices to be made. We review the rapid evolution in profiling breast cancer tissues, and discuss the current evidence for clinical use of this information and how the emerging molecular paradigm can be integrated into the clinical-pathologic context as we progress toward “precision” therapy for patients with breast cancer and other solid tumors.

Key words::

• breast cancer
• ER
• HER2
• multi-gene assay
• PR
• prognosis
• prediction
• rtPCR

Acknowledgments

The authors thank Mrs. Mary Jackson and Miss Emma Tillett for their exceptional clerical support for this work.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this paper.