Prediction and prognosis of biologically aggressive breast cancers by the combination of DWI/DCE-MRI and immunohistochemical tumor markers.

Breast cancer (BC) research has been evolving tremendously on all fronts, whether it being for imaging, pathology, oncology, pharmacology, or genetics. Regarding medical imaging, dynamic contrast enhanced MRI (DCE-MRI) and diffusion weighted imaging (DWI) are now both universally recognized and widely used modalities in multiparametric MRI (mp-MRI) to diagnose and stage BC, to assess post-chemotherapy response, and to differentiate between scar tissue and recurrent tumor. Meanwhile, pathologists have provided evidence of BC being heterogeneous and having several subtypes, which in turn might affect its prognostic and therapeutic outcomes. Immunohistochemical testing for estrogen receptor (ER), progesterone receptor (PR), human epidermal receptor factor-2 (HER-2), and Ki-67 proliferation index is performed daily to categorize breast tumors into different molecular subtypes. Since then, a number of studies have evaluated whether there is any inter-relationship between them and mp-MRI parameters, the nature of their relationship if any, and the predictive ability of mp-MRI to diagnose biologically aggressive tumors. This review aims to summarize published literature where the data of DCE-MRI/DWI and immunohistochemical markers have been combined for BC studies in order to observe what conclusions have been reached so far, how our understanding of BC has changed because of them, and what are the future implications of these for the diagnosis of breast tumors. We also give our suggestions on what other relevant areas should be investigated.