Preoperative assessment of contrast-enhanced spectral mammography of diagnosed breast cancers after sonographic biopsy: Correlation to contrast-enhanced magnetic resonance imaging and 5-year postoperative follow-up

Abstract

To assess the feasibility of using contrast-enhanced spectral mammography (CESM) for operative planning of patients with breast cancers who were initially diagnosed by sonographic guided biopsy.With the approval of the Institutional Review Board of our hospital, we retrospectively reviewed the data on patients with breast cancers who underwent CESM and contrast-enhanced magnetic resonance imaging (CE-MRI) prior to operation and were followed up for at least 5 years postoperatively. The patients with breast cancer diagnosed by sonographic guided biopsy without mammography were included for analysis. The size and number of cancers on low-energy mammograms (LE-MG), recombined subtracted mammograms (RSM), and CE-MRI were recorded and compared with microscopic histopathologic data and at least 5 years of clinical follow-up data.Fifty-one cancerous breasts of 46 patients were included in the analysis. All the principal cancers could be detected by RSM or CE-MRI; however, only 45 were by LE-MG. The Pearson correlation coefficients for the size on microscopy were 0.44 for LE-MG, 0.77 for RSM, and 0.84 for CE-MRI (all P-values ≤.001). Regarding the microscopic reports, RSM or CE-MRI had sensitivities of 100% and a positive predictive value of 63.6% for multicentric cancers. One breast cancer with partial mastectomy recurred after 3 years of follow-up.CESM was feasible for assessing the cancer extension and multicentric cancers as secondary examination in patients with diagnosed breast cancers after sonographic biopsy.

Figure 1

Pearson correlations of index cancer sizes on (A) recombined subtracted mammography (RSM); and (B) CE-MRI versus microscopy (micro). CE-MRI = contrast-enhanced magnetic resonance imaging.

Figure 2

Flow diagram of this study. Demonstrating the diagnostic accuracy comparing low energy mammogram (LE-MG), recombined subtracted mammography (RSM), and contrast-enhanced magnetic resonance imaging (CE-MRI) with microscopy results. The size correlation signifies the Pearson correlation coefficients as compared with microscopy according to size. The multicentric or multifocal diagnosis of cancer is denoted by index study/microscopy reference.

Figure 3

A 50-year-old woman. (A) LE-MG (CC view) showed dense breasts without obvious breast nodules. (B) RSM (CC view) revealed three irregular enhanced masses in the inner region and subareolar region of the left breast. (C) CE-MRI with three-dimensional reconstruction displayed three enhanced masses corresponding to RSM. Finally, pathology confirmed that the two masses at the inner region were cancers and the mass at the subareolar region was a benign papillary tumor. CE-MRI = contrast-enhanced magnetic resonance imaging, LE-MG = low-energy mammography, RSM = recombine subtracted mammography.

Figure 4

A 38-year-old woman. (A) LE-MG (CC view) showed dense breasts with an irregular hyperdense patch of tissue distortion in the inner region of the left breast. (B) RSM (CC view) revealed a remarkable segmental enhancement in the inner region and multiple nodular enhancement in the outer region of the left breast. The patient requested partial mastectomy due to impalpable, negative sonography, and conventional mammography. The cancer was confirmed to be invasive ductal carcinoma. (C) CE-MRI 3 years after treatment demonstrated a non-mass enhanced recurrent cancer in the outer region of the left breast. CE-MRI = contrast-enhanced magnetic resonance imaging, LE-MG = low-energy mammography, RSM = recombine subtracted mammography.