الفهرس 
Introduction and aim of work.Only 14 pages are availabe for public view
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Abstract
Breast cancer is the most prominent cancer and the second most
prominent cause of mortality in women. In recent years the incidence of
breast cancer has increased to102 per 100,000 per year. Early diagnosis
and accurate follow-up of these patients are important for efficient patient
management.
Early detection is the most effective strategy for reducing mortality
from breast cancer. At present, mammography is the only screening
method that has been shown to affect patient survival.
However, this technique has a low specificity, and about 10% of
breast carcinomas cannot be identified by mammography even if palpable
(>1cm in diameter).To overcome this limitation, other diagnostic
techniques, such as computed tomography (CT), ultrasound (US),
magnetic resonance (MR) & positron emission tomography (PET) are
being used.
PET with 2-[fluorine-18] fluoro-2-deoxy-D-glucose (FDG) has
been recognized as a useful diagnostic technique in cancer imaging.
In patients with breast cancer, PET has been used for diagnosis,
staging, monitoring response to therapy, restaging patients with breast
cancer.
A major advantage of FDG PET imaging compared with
conventional imaging is that it screens the entire patient for local
recurrence, lymph node metastases and distant metastases during a single
whole body examination using a single injection of activity, with a
reported average sensitivity and specificity of 96% and 77%,
Summary & conclusion
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respectively. In most studies the sensitivity of FDG PET is higher than
that of a combination of conventional imaging methods.
Despite its high sensitivity for the detection of malignant diseases,
PET is occasionally not able to differentiate increased but physiologic
uptake from malignant lesion and the capability of PET to depict lesions
smaller than 1cm in diameter is constrained by limited spatial resolution.
Conventional imaging modalities such as mammography and US
rely primarily on changes in anatomic structure for disease detection.
FDG PET can help detect accelerated metabolic activity that occurs
before anatomic structural changes; however, because of the expense of
the examination and the radiation exposure involved, it is not generally
suitable for routine screening purposes.
The combination of metabolic and morphological imaging within
the same patient position following image fusion should be advantageous
in terms of exact localization of lesions and, in turn, reduction in
interpretative pitfalls
PET/CT is a unique combination of the cross sectional anatomy
provided by CT and the metabolic information provided by PET which
are acquired during a single examination.
Synergistic advantage of adding CT is that the attenuation
correction needed for PET can also be derived from the CT data, an
advantage not obtainable by integrating PET and magnetic resonance
imaging. This makes PET/CT 25%-30% faster than PET alone with
standard attenuation-correction methods, leading to higher patient
throughput and a more comfortable examination.
Summary & conclusion
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PET/CT added incremental diagnostic confidence to PET in 60%
of patients and in more than 50% of regions with increased FDG uptake.
PET/CT correctly detected more regions with malignancies than did CT,
and 28% of the malignant regions with positive PET/CT findings showed
equivocal or negative CT findings