Paul E Summers1, Andrea Vingiani2, Salvatore Di Pietro3, Andrea Martellosio4, Pedro F Espin-Lopez4, Simona Di Meo5, Marco Pasian5, Michele Ghitti6, Marco Mangiacotti6, Roberto Sacchi6, Paolo Veronesi7, Maurizio Bozzi5, Andrea Mazzanti5, Luca Perregrini5, Francesco Svelto5, Lorenzo Preda8, Massimo Bellomi9, Giuseppe Renne2. 1. Division of Radiology, IEO, European Institute of Oncology IRCCS, Milan, Italy. Electronic address: paul.summers@ieo.it. 2. Division of Pathology, IEO, European Institute of Oncology IRCCS, Milan, Italy. 3. Post-graduate School of Radiodiagnostics, University of Milan, Milan, Italy. 4. Division of Radiology, IEO, European Institute of Oncology IRCCS, Milan, Italy; Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy. 5. Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy. 6. Applied Statistics Unit, Department of Earth and Environmental Sciences, University of Pavia, Pavia, Italy. 7. Division of Senology, IEO, European Institute of Oncology IRCCS, Milan, Italy. 8. Division of Radiology, IEO, European Institute of Oncology IRCCS, Milan, Italy. 9. Division of Radiology, IEO, European Institute of Oncology IRCCS, Milan, Italy; Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy.
Abstract
PURPOSE: The evaluation of the surgical margin in breast conservative surgery is a matter of general interest as such treatments are subject to the critical issue of margin status as positive surgical margins can undermine the effectiveness of the procedure. The relatively unexplored ability of millimeter-wave (mm-wave) spectroscopy to provide insight into the dielectric properties of breast tissues was investigated as a precursor to their possible use in assessment of surgical margins. METHODS: We assessed the ability of a mm-wave system with a roughly hemispherical sensitive volume of ∼3 mm radius to distinguish malignant breast lesions in prospectively and consecutively collected tumoral and non-tumoral ex-vivo breast tissue samples from 91 patients. We characterized the dielectric properties of 346 sites in these samples, encompassing malignant, fibrocystic disease and normal breast tissues. An expert pathologist subsequently evaluated all measurement sites. RESULTS: At multivariate analysis, mm-wave dielectric properties were significantly correlated to histologic diagnosis and fat content. Further, using 5-fold cross-validation in a Bayesian logistic mixed model that considered the patient as a random effect, the mm-wave dielectric properties of neoplastic tissues were significantly different from normal breast tissues, but not from fibrocystic tissue. CONCLUSION: Reliable discrimination of malignant from normal, fat-rich breast tissue to a depth compatible with surgical margin assessment requirements was achieved with mm-wave spectroscopy.
PURPOSE: The evaluation of the surgical margin in breast conservative surgery is a matter of general interest as such treatments are subject to the critical issue of margin status as positive surgical margins can undermine the effectiveness of the procedure. The relatively unexplored ability of millimeter-wave (mm-wave) spectroscopy to provide insight into the dielectric properties of breast tissues was investigated as a precursor to their possible use in assessment of surgical margins. METHODS: We assessed the ability of a mm-wave system with a roughly hemispherical sensitive volume of ∼3 mm radius to distinguish malignant breast lesions in prospectively and consecutively collected tumoral and non-tumoral ex-vivo breast tissue samples from 91 patients. We characterized the dielectric properties of 346 sites in these samples, encompassing malignant, fibrocystic disease and normal breast tissues. An expert pathologist subsequently evaluated all measurement sites. RESULTS: At multivariate analysis, mm-wave dielectric properties were significantly correlated to histologic diagnosis and fat content. Further, using 5-fold cross-validation in a Bayesian logistic mixed model that considered the patient as a random effect, the mm-wave dielectric properties of neoplastic tissues were significantly different from normal breast tissues, but not from fibrocystic tissue. CONCLUSION: Reliable discrimination of malignant from normal, fat-rich breast tissue to a depth compatible with surgical margin assessment requirements was achieved with mm-wave spectroscopy.