CT scanning for Colon and Rectal cancer
Computerised Axial Tomography (CT) scanning.
CT scanning is a type of Xray investigation which produces images of the internal organs of the body. Developed by Sir Geoffery Hounsfield, the first commercial scanner built by EMI was comissioned in 1971. CT scanning has developed extensively since then and now forms the mainstay of coloncancer imaging.
CT scanning is used to assess the spread or "stage" of colon and rectal cancer. A staging CT scan will include the chest, abdomen and pelvis and will give an indication of the size and site of the primary tumour, the presence of enlarged lymph nodes and the presence of spread of the cancer to the Liver or Lungs (metastases).
A CT scan of the chest showing a single metastasis in the left lung
A CT scan of the liver showing multiple metastases (arrowed) (NEJM)
A staging CT scan will be undertaken before surgery for colon cancer and repeated as part of the follow up investigations following surgery.