Editor:
We have several concerns about the recent article by Dr Phillips and colleagues, published in the November 2023 issue of Radiology (1). This reader study compared two-dimensional (2D) mammography, contrast-enhanced mammography (CEM), abbreviated MRI, and MRI, concluding that CEM was noninferior to MRI in an asymptomatic study sample. Several methodologic issues warrant clarification and call this conclusion into question.
The reader study appears to have significant selection bias. In the listed detection method (Table S1 in Phillips et al), 35 of 44 patients with cancer were recruited due to abnormal mammographic findings. If correct, this is not representative of women imaged with MRI. MRI helps to detect approximately 16 additional cancers per 1000 women screened. By including primarily cancers depicted at screening mammography and US, the study fails to address the key clinical question: Does screening CEM truly find the small early cancers missed at conventional breast imaging and depicted at MRI? To state that “the results are a key step toward the replacement of screening breast MRI [with CEM]” is unsubstantiated.
The article also does not compare CEM versus MRI and 2D mammography, the current standard of care when MRI is used for supplemental screening. In Table S1 in Phillips et al, nine of 44 cancers presented as “calcifications.” MRI is a supplement, not a replacement, to screening mammography because we know MRI will not depict some cancers manifesting as mammographic calcifications. Having microcalcifications in 20% of the cancer cohort in this report raises concerns about the fundamental validity of the study’s conclusion.
We request that the authors adjust their conclusions based on the inherent design limitations. We also ask that Figure 3 be updated to include a receiver operating characteristic curve of MRI with 2D mammography to better understand if, indeed, screening CEM is noninferior to the current standard of care in high-risk patients.
Footnotes
Disclosures of conflicts of interest: S.E.W. No relevant relationships. M.S.J. Speaker honorarium from GE HealthCare. K.P. Grants from Digital Hybrid Breast PET/MRI for Enhanced Diagnosis of Breast Cancer (HYPMED) H2020 Research and Innovation Framework Program (PHC-11-2015 #667211-2); A Body Scan for Cancer Detection using Quantum Technology (CANCERSCAN) (H2020-FETOPEN #828978); Multiparametric 18F-Fluoroestradiol PET/MRI coupled with Radiomics Analysis and Machine Learning for Prediction and Assessment of Response to Neoadjuvant Endocrine Therapy in Patients with Hormone Receptor+/HER2− Invasive Breast Cancer Jubiläumsfonds of the Austrian National Bank (18207); Vienna Science and Technology Fund (LS19-046); MSKCC 2020 Molecularly Targeted Intra-Operative Imaging Award; Breast Cancer Research Foundation June 2019 to May 2021; NIH (UG3 CA239861); NIH (R01 CA249893); NIH (1R01CA270018-01A1); supported in part through the NIH/NCI Cancer Center (P30 CA008748); MSK has institutional financial interests relative to GRAIL; consultancy from Genentech, Merantix Healthcare, Aura Health Technologies, Guerbet; speakers bureaus fees from European Society of Breast Imaging, Bayer, Siemens Healthineers, DKD, Olea Medical, and Roche; support for travel and/or meetings from European Society of Breast Imaging; participation on a DataSafety Monitoring Board from Guerbet, Bayer; executive board membership, EUSOBI. J.S.S. No relevant relationships. C.C. Personal fees for advisory board from Bayer; consultant for Guerbet; speakers bureau fees from GE Medical.
Reference
- 1. Phillips J , Mehta TS , Portnow LH , Fishman MDC , Zhang Z , Pisano ED . Comparison of Contrast-enhanced Mammography with MRI Utilizing an Enriched Reader Study: A Breast Cancer Study (CONTRRAST Trial) . Radiology 2023. ; 309 ( 2 ): e230530 . [DOI] [PubMed] [Google Scholar]