الفهرس 
Chapter 1: Introduction and Aim of the workOnly 14 pages are availabe for public view
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Abstract
The use of mammography in breast cancer screening has been shown to reduce mortality in women over the age of 40. In certain patient populations, conventional full-field digital mammography has shown additional benefits in the ability to detect cancer and is currently the standard of care for breast cancer screening. However, conventional mammography is an imperfect modality and has been criticized for its false positive rate and sensitivity, especially in women with dense tissue. Digital breast tomosynthesis promises to address both of these concerns
Tomosynthesis images are obtained in the same craniocaudal and mediolateral oblique projections as the conventional mammography. Digital Breast Tomosynthesis (DBT) reduces the obscuring effect of overlying and underlying breast tissue. Elimination of superimposed breast tissue improves the detection of lesions, otherwise hidden by the dense parenchyma, and the cancer visibility on DBT is significantly superior to Full-Field Digital Mammography.
Digital breast tomosynthesis can offer user-friendly and surgical advantages over ultrasound and MRI because it is an integral part of next-generation mammography units. In tomosynthesis, mammographic projections are taken at different angles to create a three-dimensional image of the breast during standard compression mammography. It may be of particular interest in evaluating women with dense breasts, as it partially overcomes the masking effect seen in mammography.
Digital Breast Tomosynthesis (DBT) reduces the number of false-positive interpretations caused by superimposed breast tissue, reducing the need for recall and diagnostic work-up for lesions that would, otherwise, have led to call-back if Full-Field Digital Mammography (FFDM) had been used alone.
There is strong evidence that screening mammography is less sensitive in women aged 40 to 49 years and/or with heterogeneous or extremely dense breast tissue, limiting the applicability and usefulness of screening in these groups. The decreased sensitivity is
Summary & Conclusion
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caused by the so-called ”masking effect” of breast cancer, which is caused by overlapping with normal breast tissue and is most pronounced in extremely dense breast parenchyma
The main aim of the present study was to compare the cancer detection rates of digital breast tomosynthesis plus conventional digital mammography with those of conventional digital mammography alone.
Our study concluded that the patients were distributed according to biopsy outcomes into 27 (77.1%) positive and 8 (22.9%) negative, while the patients were distributed according to the combined (DBT + DM) outcome into 26 (74.3%) suspicious and 9 (25.7%) not suspicious, and when the assessment was according to (DM) alone, it resulted in 23 (65.7%) suspicious and 12 (34.3%) not suspicious.
On assessing the diagnostic performance, the present study found that sensitivity and specificity of the combined (DBT + DM) assessment was 92.6% and 87.5% respectively for detection of cancer breast. While the sensitivity and specificity of (DM) alone was 77.8% and 75% respectively for detection of cancer breast.
Conclusion & Recommendations
Digital Breast Tomosynthesis (DBT) improves the clinical accuracy of mammography by increasing both sensitivity and specificity, possibly due to improved image visibility and quality.
This study results encourage us to recommend health care institutions to upgrade to use DBT not only for diagnosis, but also for breast cancer screening.