الفهرس 
Anatomical BackgroundOnly 14 pages are availabe for public view
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Abstract
Carcinoma of the breast is the most common cancer in women.
Early and accurate detection of breast cancer is critical to the treatment and, ultimately survival of patients.
In recent years, imaging with positron emission tomography (PET) for tumor staging and therapy control has been introduced. Rather than anatomic information, it provides physiologic information on glucose uptake and metabolism.
PET/CT has advantages over other imaging methods; it can differentiate benign from malignant lesions, staging and restaging tumors, detect functional changes before there is any change in clinical or radiological size of a mass, better in identify cancer that has spread, making up treatment plane and monitoring tumor response, detect tumor recurrence early and distinguish viable metabolically active tissue from scars.
In patients who have locally advanced breast cancer, PET-CT accurately determines the extent of disease, particularly the loco-regional lymph node status.
FDG-PET-CT is generally more sensitive in the detection of distant metastases than conventional imaging, and is therefore a more accurate method of determining the true extent of disease. One exception is the detection of sclerotic bone metastases; these lesions are often not metabolically active enough for FDG-PET detection, but are readily detected by bone scintigraphy.
FDG-PET-CT seems to be highly useful for monitoring response to therapeutic interventions. This technique can identify response to therapy earlier than any other imaging method currently available which greatly improves patient management by allowing termination of ineffective and toxic therapies.
The SUV is a semi quantitative assessment of the radiotracer uptake from a static PET image. Typically, malignant tumors have an SUV of greater than 2.5-3.0, whereas normal tissues SUVs ranging from 0.5 to 2.5.
An SUV of 1 means uniform distribution. An SUV greater than 2.5 has been associated with cancer, but many factors can affect the reliability of SUV, however, it is best to use SUV as a guide to interpretation rather than an absolute value. In general it appears that SUV of benign lesion is lower than that of the malignant lesion,
PET scans are not used to screen women for breast cancer. The test has only a limited ability to detect small tumors. PET scans can be useful for evaluating people after breast cancer has already been diagnosed, in cancer has spread to the lymph nodes, metastatic spread and response to treatment.
18-FES detects estrogen receptor at tumor site and complementary to FDG in assessment of recurrent and metastatic cancers as well as response to therapy.
FDG-PET/CT detects cancer spread in its earliest stages when changes are happening at a functional and cellular level.
PET/CT is superior to PET and CT alone, in the diagnosis and treatment of various primary or metastatic cancers. Thus, PET/CT is a more accurate test than either of its individual components.
PET-CT proved to be helpful in the evaluation of anatomic regions that have been previously treated by surgery or radiation in which the discrimination between post-treatment scar and recurrent tumor can be problematic.