الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Breast carcinoma is the most common cancer in women. It is currently second only to lung cancer as a cause of cancer death in women,
Conventional imaging modalities as mammography and ultrasound remain the method of choice for routine screening programs and is the 1st imaging aid, but conventional assessment have well-known limitations, such as inaccurate differentiation between benign and malignant lesions and estimation of the size of malignant tumors.
Mammography is the established screening tool for breast cancer. It is sensitive to early indications of disease but in many cases the findings are not sufficiently specific so subsequent diagnostic work up is required. Ultrasound is the primary adjunctive tool to mammography for diagnosis of suspicious findings. However, until recently, there was still large number of cases diagnosed as indeterminate lesions after complementary ultrasound.
Ultrasonography is an in-expensive, effective, noninvasive method that plays a very important role in the evaluation of Breast Cancer, the evaluation of palpable masses that are mammographically occult, differentiating cystic from solid breast masses and provides valuable information about the nature and extent of Solid Masses. yet the differentiation of benign versus malignant breast lesion is still a limited application for conventional ultrasound.
Elastography is an effective , convenient technique that when added to breast ultrasound, helps distinguish cancerous breast lesions from benign ones. It improves ultrasound’s specificity by utilizing conventional ultrasound imaging to measure the compressibility and mechanical properties of a lesion. Since cancerous tumors tend to be stiffer than the surrounding healthy tissues, a more compressible lesion on elastography is less likely to be malignant. Elastography provides information of tissue hardness , in addition to shape and vascularity that were determined with conventional ultrasound.,In practice, it is not used independently but as an additional role for conventional ultrasound
The sensitivity of breast MRI for the detection of cancer is the greatest of all imaging techniques and when the findings of conventional imaging are inconclusive (i.e. BI-RADS 0), MRI can be used as a problem-solving modality, it is also better at identifying the true extent of cancer when multifocal disease or ductal carcinoma in situ is present.
Diffusion-weighted imaging (DWI), if further clinical evaluation is needed, represents an easy non time consuming complementary quantitative breast imaging sequence. Based on diffusion properties; ADC mapping provides valuable information on benign and malignant lesions by characterizing tumor cellularity. DWI has high specificity for breast malignant lesions and has the potential to analyze cancer extension. It must be understood that DWI can’t stand alone as a diagnostic criterion to avoid non visualization of small breast lesions ,thus it must conjugate with contrast enhanced MRI.
MRS provides a method for characterizing the chemical composition of breast cancer in vivo. Although MRS is frequently used in the clinical management of some tumors, such as brain tumors, breast MRS is just emerging as a clinically practical tool highly complementary to breast MRI. In addition, there is early but very promising work using MRS to monitor response to therapy, emphasizing that biochemical changes associated with disease response or progression precede anatomical changes (i.e., a change in tumor size).
With the newest PET/CT system having spatial resolution as good as 4mm the detection of small lesions may be partially improved, so PET/CT appeared preferable to PET or CT in diagnosing breast cancer. The diagnostic accuracy of PET/CT in axillary lymph node metastases is 83% with 58% in sensitivity and 95% in specificity. Advantage of whole-body PET imaging over conventional imaging modalities is its ability to detect metastasis at different sites and organs during a single examination, its sensitivity for detecting distant metastasis is 85% and its specificity is 79%. Sensitivity and specificity of PET for detecting recurrence are 84% and 78%, respectively, whereas the sensitivities and specificities of the conventional imaging modalities are 63% and 61%.
interventional imaging permits the logical management of possibly malignant abnormalities, The two principle imaging modalities are ultrasound and X-ray stereotaxis. The use of magnetic resonance imaging is limited by its cost and the availability of equipment and this would not be a routine imaging modality. Ultrasonography is the modality of choice as it is easier to perform, more comfortable for the patient and less time-consuming. For MRI-detected lesions that can’t be seen on sonography, biopsy can be performed under MRI guidance.