High contralateral parenchymal enhancement (CPE) on dynamic contrast-enhanced magnetic resonance imaging (MRI) in patients with breast cancer is significantly associated with long-term outcomes, researchers from the University Medical Centre Utrecht in the Netherlands have reported.1,2 The reason why remains unknown and elusive. Their recent research has ruled out the association of CPE and tumor-derived estrogen receptor (ER) pathway activity in patients with early stage invasive ER-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer.3
Multiple studies have linked CPE with breast cancer risk and with prognostic factors such as tumor grade and progesterone receptor status. Principal investigator Bas H.M. van der Velden, PhD, Kenneth Gilhuijs, PhD, and colleagues hypothesized that high CPE would facilitate transport of endocrine therapy drugs while low CPE would not. The results could help explain why some patients do not benefit from endocrine therapy. The genomic ER-pathway activity is a measure of intrinsic sensitivity of a tumor to endocrine therapy.
Reporting study details in the October 16, 2019, online edition of the European Journal of Radiology, the authors said they could not find associations between levels of CPE on MRI and genetic ER pathway activity of the tumor. They compared and analyzed CPE data with ER-factors derived from multiomics data and the Sensitivity to Endocrine Therapy (SET)-index of 227 patients.
“Patients with high CPE did not have a different SET-index or ER-factor than patients with low CPE,” wrote the authors.
“Since our results do not suggest parenchymal enhancement and ER-pathway activity to be interchangeable; they may be complimentary,” they wrote. “Future research should address the potentially complimentary value of these biomarkers.”
MRI contralateral parenchymal enhancement not explained by ER pathway activity in breast cancer patients. Appl Radiol.