Full Field Digital Mammography (FFDM) versus CMOS Technology, Specimen Radiography System (SRS) and Tomosynthesis (DBT) - Which System Can Optimise Surgical Therapy?

Abstract

Aim: This prospective clinical study aimed to evaluate whether it would be possible to reduce the rate of re-excisions using CMOS technology, a specimen radiography system (SRS) or digital breast tomosynthesis (DBT) compared to a conventional full field digital mammography (FFDM) system. Material and Method: Between 12/2012 and 2/2013 50 patients were diagnosed with invasive breast cancer (BI-RADS™ 5). After histological verification, all patients underwent breast-conserving therapy with intraoperative imaging using 4 different systems and differing magnifications: 1. Inspiration™ (Siemens, Erlangen, Germany), amorphous selenium, tungsten source, focus 0.1 mm, resolution 85 µm pixel pitch, 8 lp/mm; 2. BioVision™ (Bioptics, Tucson, AZ, USA), CMOS technology, photodiode array, flat panel, tungsten source, focus 0.05, resolution 50 µm pixel pitch, 12 lp/mm; 3. the Trident™ specimen radiography system (SRS) (Hologic, Bedford, MA, USA), amorphous selenium, tungsten source, focus 0.05, resolution 70 µm pixel pitch, 7.1 lp/mm; 4. tomosynthesis (Siemens, Erlangen, Germany), amorphous selenium, tungsten source, focus 0.1 mm, resolution 85 µm pixel pitch, 8 lp/mm, angular range 50 degrees, 25 projections, scan time > 20 s, geometry: uniform scanning, reconstruction: filtered back projection. The 600 radiographs were prospectively shown to 3 radiologists. Results: Of the 50 patients with histologically proven breast cancer (BI-RADS™ 6), 39 patients required no further surgical therapy (re-excision) after breast-conserving surgery. A retrospective analysis (n = 11) showed a significant (p < 0.05) increase of sensitivity with the BioVision™, the Trident™ and tomosynthesis compared to the Inspiration™ at a magnification of 1.0 : 2.0 or 1.0 : 1.0 (tomosynthesis) (2.6, 3.3 or 3.6 %), i.e. re-excision would not have been necessary in 2, 3 or 4 patients, respectively, compared to findings obtained with a standard magnification of 1.0 : 1.0. Conclusion: The sensitivity of the BioVision™, the Trident™ and tomosynthesis was significantly (p < 0.05) higher and the rate of re-excisions was reduced compared to FFDM using a conventional detector at a magnification of 2.0 but without zooming.

Keywords: Breast; breast cancer; breast malignancy; mammography.

Fig. 1

Specimen radiograph. Inspiration™, magnification 1.0 : 2.0, invasive breast carcinoma pT1cN0M0, diameter 1.6 cm; it is not possible to determine the length of the spicules (arrows) and differentiate them from surrounding tissue.

Fig. 2

BioVision™ and Trident™: magnification 1.0 : 2,0, invasive breast carcinoma pT1cN0M0, diameter 1.6 cm; the spicules (arrows) are clearly visible and easily differentiated from the surrounding tissue. Identical images were created when both systems (BioVision™ and Trident™) were used under the same assessment conditions (expansion of the publication by Schulz-Wendtland R et al. Geburtsh Frauenheilk 2012; 72: 532–538).

Fig. 3

Tomosynthesis, image 7 of 25; magnification 1.0 × 1.0, invasive breast carcinoma pT1cN0M0, diameter 1.6 cm; the spicules (arrows) were clearly visible and could be differentiated well from the surrounding tissue (using imaging and confirmed by histological investigation). The guide wire was removed in Figs. 1 to 3 to show how the differentiation of the tumor from the surrounding tissue.