SEER Training Modules


Computerized axial tomography (CT) scanning is used for the examination of many parts of the body. The scan's images show cross-sectional 'slices" of the body that are each a millimeter thick. A composite image is created by the computer and photocopied. The CT scan gives an accurate picture of the extent of the disease and helps identify tumors at an early stage. CT scans are performed both with and without contrast media. CT scans can be taken of the head, chest, abdomen, pelvis, or the whole body. When a case is tagged, the entire report should be reviewed for correct interpretation of the areas that are involved or not involved with tumor. Enlarged lymph nodes may also be seen on the CT scans.

Diagnostic nuclear medicine examinations or scans are used to identify abnormalities in the brain, salivary glands, thyroid, heart, lung, kidney, liver, spleen, and bone. The patient is given a radioisotope that emits gamma rays and permits the radiologist to see abnormal structures or functions. Bone scans can show metastatic lytic (destructive) lesions or blastic (overgrowth of bone) lesions of bone. For example, breast and prostate cancers are known to metastasize to the bone. Therefore, a bone scan may confirm or rule out the distant spread of the disease. Liver and spleen scans show the presence and size of a tumor. Brain scans can indicate the location of a tumor, size, and associated vascular structures.