Purpose: To evaluate the effect of background parenchymal enhancement (BPE) on cancer detection in patients undergoing magnetic resonance imaging (MRI) guided biopsy for lesions that were detected on MRI but were not appreciated on other modalities, such as mammography (MG) or ultrasound (US).
Methods: Analysis of 144 MRI guided biopsies for high risk lesions on MRI, that were not visible on MG or US was conducted. The procedures were performed in Wolfson Medical Center by 2 experienced breast radiology specialists during January 2017 to December 2018 and recorded retrospectively. Pathology was compared between premenopausal and postmenopausal women with low BPE (mild or minimal) to high BPE (moderate to marked) by using Fisher’s exact test.
Results: Of 100 MRI guided biopsies in the postmenopausal group, 89 were classified as having low BPE and 11 were classified as having high BPE (89% vs. 11% respectively). Of 44 biopsied in the premenopausal group, 36 were classified as having low BPE and 8 were classified as having high BPE (81.8% vs. 18.2% respectively). For postmenopausal patients the malignancy detection in low versus high BPE was 40 versus 5 biopsies (44.9% vs. 45.5%, p>0.999). Whereas for premenopausal patients the malignancy detection in low versus high BPE was 9 versus 1 (25% vs 12.5%, p=0.659).
Conclusion: In postmenopausal women different BPE levels had no significant impact on rates of breast cancer in MRI guided biopsy for high risk lesions detected only on MRI.
In the subgroup of premenopausal women, undergoing MRI guided biopsies, high levels of BPE have an inclination to be associated with lower rates of breast cancer while lower BPE were associated with increased breast cancer prevalence. Larger samples are needed to test with sufficient power whether the observed differences are statistically significant.
