The Value of Dynamic Contrast-Enhanced MRI in the Diagnosis and Management of Triple Negative Breast Cancer

Abstract

SUMMARY & CONCLUSION N owadays, TNBC is one of the most attractive areas of research. Reasons for this scientific interest are the lack of a recognized target for molecular-oriented therapy, which makes TNBC a new orphan disease; therefore it represents an important clinical challenge because these cancers do not respond to endocrine therapy or other available targeted agents. Considering the gene-expression analysis, it appears very clear that TNBC is a heterogeneous BC form, which shows only partial overlapping features with so-called basal-like (BL) breast cancer. Triple negative phenotype is characterized by distinct clinical, histopathological and molecular characteristics, and is associated with the development of recurrence and distant metastases, and a poorer prognosis. Better understanding of the imaging features of TN cancers especially at MRI, provides an imaging biomarker with clinical implications. This study aimed to determine the dynamic contrast-enhanced magnetic resonance imaging features of TN breast cancers in comparison to other breast cancer subtypes and to evaluate the DCE-MRI impact on management of such cases, especially in detection of response after NAC.

TNBC presents several MRI features on DCE-MRI such as multiple lesions, mass enhancing type, irregular shape, not circumscribed margin, rim enhancement, high T2 signal intensity and malignant kinetic curve pattern. In this study we demonstrate certain MRI features with significant differences that are more frequent with Triple negative breast cancer compared with other breast cancer subtypes such as round shape mass lesion, mass with rim enhancement in post contrast images and intratumoral bright signal intensity on T2 weighted images. While other DCE-MRI parameters show no statistically differences between TN and non-TN breast cancer, which are distribution of FGT and BPE, mass margin, non mass enhancement distribution and enhancement pattern, lymph nodes status and types of kinetic curves. To summarized, DCE –MRI is an accurate modality in identifying different types of breast cancers and their extent and multiplicity when there are undetermined on other modality. Also, it is most sensitive modality for identifying TNBC as it shows its malignant features and it is an accurate promising tool to evaluate tumor extent and response after NAC, and it is an accurate promising tool to evaluate residual tumor or recurrence postoperatively. MRI assessment is a valuable tool to detect response after neoadjuvant chemotherapy, which affected the management of breast cancer cases especially triple negative BC.