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How are CT scans used to find tumors?

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Precancerous growth in a human colon — cancer View through an endoscope of a polyp, a benign precancerous growth projecting from the inner lining of the colon.

Computed tomography (CT) scans are highly effective for identifying tumours because they overcome the limitations of conventional X-ray systems, which often obscure internal structures with overlapping shadows from bones and organs.12

In a CT scan, a narrow beam of X-rays rotates around the patient, while hundreds of detectors measure the radiation that passes through the body from many different angles. A computer then integrates this data to assess the density of tissues at thousands of points, reconstructing the information into a detailed, two-dimensional cross-sectional image.231

By providing these clear, plane-specific views, CT scanning allows physicians to visualize and locate masses or space-occupying lesions with much greater precision than standard imaging. This diagnostic capability is particularly valuable for evaluating abdominal tumours and other abnormalities, often enabling detection without the need for exploratory surgery.12