الفهرس 
GROSS ANATOMY OF THE COLON AND THE RECTUMOnly 14 pages are availabe for public view
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Abstract
Colorectal cancer is the third leading cause of cancer worldwide and
recurrence of colorectal cancer occurs in about one-third of patients within the
first 2 years after surgery. Farly detection of recurrent colorecral carcinoma has
become more important as the treatment options for localized disease have
improved significantly.
Positron emission tomography (PET) for tumor staging and therapy
control has been introduced. Rather than anatornic information, it provides
physiologic information on glucose uptake and metabolism. The major
advantage of Pl~T/CT is that both metabolic and anatornic information for the
same body region are obtained at nearly the same time. ’It facilitates the
separation of normal physiologic uptake Irorn pathologic uptake, provides
accurate localization or functional abnormalities and reduces the incidence of
false-positive and false-negative imaging studies.
There are different methods for assessment of radiotracer uptake by
normal and pathologic tissues, such as visual inspection & the standardized
uptake value (SlJV). SUV is a simplified index or I gr-FDG uptake and
provides a relative indication or the degree of metabolism within the lesion
being evaluated.
PET/eT can be used in detection of recurrence of colorecral cancer, as
early detection of the disease with frequent follow-up is believed to have an
important effect on outcome as early therapy is more effective than delayed
therapy. 11 also-can detect lesions that are usually overlooked in C’T such as
FDG-avid normal-sized lymph nodes (usually <1 cm) & peritoneal lesions, it
also has importance in adding additional findings to inconclusive C’l’ finding. It
is extremely useful for therapy response assessment due to its capacity to help
distinguishing between residual meiabolically active tumor and areas.