الفهرس 
Colorectal anatomyOnly 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 and resection of isolated metastases is
associated with survival improvement while multifocal metastatic lesions are
associated with less favorable prognosis.
Early detection of recurrent colorectal carcinoma has become more
important in the past decade, as the treatment options for localized disease
have improved significantly; therefore detection of tumor sites throughout the
body is needed with high sensitivity and specificity.
Preoperative chemoradiotherapy is increasingly used in patients with
colorectal carcinoma and assessment of the therapeutic response is
fundamental in order to change an ineffective but possibly toxic
chemotherapy protocol or to decide surgical resection.
Most radiologic procedures map the anatomy and morphology of
tumors with little or no information about their metabolism. 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. The
main drawback of PET in tumor imaging is the virtually complete absence of
anatomic landmarks, which impedes precise localization of lesions.