Breast Radiation Exposure of 3D Digital Breast Tomosynthesis Compared to Full-Field Digital Mammography in a Clinical Follow-Up Setting

Appropriate screening mammography method for patients with breast implants

In this study, we aimed to evaluate the benefits and losses of mammography with and without implant displacement (ID) and propose an appropriate imaging protocol for the screening of breasts with implants. We evaluated mammograms of 162 breasts in 96 patients including 71 breasts with biopsy-proven cancers. Mammography of each breast included standard MLO and ID MLO images. We reviewed the mammograms using clinical image quality criteria, which consist of parameters that evaluate the proper positioning of the breast and the image resolution. Standard MLO images showed significantly higher scores for proper positioning but showed significantly lower scores for image resolution than the ID MLO images. Moreover, standard MLO images showed significantly higher kVp, mAs, and compressed breast thickness than the ID MLO images. The organ dose was also higher in the standard MLO images than in the ID MLO images, but the difference was not statistically significant. In mammography with proven cancer, ID MLO images showed significantly higher degree of cancer visibility than standard MLO images. For screening mammography in patients with breast implants, ID MLO view alone is sufficient for MLO projection with reducing the patient's radiation dose without compromising the breast cancer detection capability, especially in dense breasts with subpectoral implants.

Impact of tomosynthesis on the evolution of the cancer detection rate in the French National Breast Cancer Screening Program

OBJECTIVES

This study aims to evaluate the cancer detection rate in French National Breast Cancer Screening Program, especially the cancer detection rate during second reading session (Reading 2) based on digital technologies used in radiology centres.

STUDY DESIGN

This was an analytical and descriptive study.

METHODS

Cancer detection rate was estimated by the ratio between the number of cancers detected and the number of women screened. The positive predictive value (PPV) was estimated as cancer detection rate among abnormal Reading 2. The relationship between Reading 2's PPV and the predictive factors was evaluated using multilevel mixed-effects logistic regression.

RESULTS

A total of 1,380,006 digital mammograms were retained in the analysis between 2010 and 2019. Cancer detection rate represented 7.8‰ at first reading session (Reading 1) and 0.5‰ at Reading 2. Cancer detection rate is significantly associated with the use of tomosynthesis (P < 0.001) at Reading 1, and differences appear within different tomosynthesis brands (P = 0.007). Reading 2's PPV differs significantly according on technologies used by first Reader (P < 0.004). Nevertheless, Reading 2 has 1.9 (1.5-2.4) more likely to predict a cancer with the presence of previous mammogram compared with those without previous images.

CONCLUSION

Using tomosynthesis technology improves cancer detection rate at Reading 1, even if differences are noticeable between brands. Using tomosynthesis technology at Reading 1 reduces Reading 2's PPV and cancer detection rate at Reading 2.