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How We Diagnose Colon Cancer

  • If you are diagnosed with colon cancer, our team often uses a series of tests to better help understand the extent of the disease and determine the right treatment for you. Some or all of these tests are needed to stage (find out the extent of) the cancer:

    • History and physical exam: Taking a thorough medical history is important to help make a treatment plan appropriate for your body and your goals. Your health care provider examines your body to check general signs of health, including signs of disease, such as lumps and swollen lymph nodes.
    • Blood chemistry studies: Your doctor takes a blood sample to check the amounts of certain substances released into the blood by organs and tissues in the body.
    • Complete blood count (CBC): Your doctor takes a sample of blood to check for the number of red blood cells, white blood cells, and platelets.
    • Carcinoembryonic antigen (CEA) assay: A test that measures the level of CEA in the blood. CEA is released into the bloodstream from both cancer cells and normal cells. When found in higher than normal amounts, it can be a sign of colon cancer and can be used to determine how a patient's treatment is progressing.
    • Biopsy: If you were diagnosed by a sigmoidoscopy or colonoscopy, a biopsy was likely already taken and sent to pathology to look at the cells under a microscope. However, after diagnosis, other biopsies may be needed if abnormalities are found elsewhere in order to test determine the right treatment.
    • Radiology exam: Common radiology procedures include:
      • Chest x-ray: An x-ray of the organs and bones inside the chest. An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body.
      • CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine.
      • MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed images of areas inside the body.
      • PET scan (positron emission tomography scan): A procedure to find malignant tumor cells in the body. A small amount of radionuclide glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the image because they are more active and take up more glucose than normal cells.
       

    At the Colon and Rectal Cancer Center at Dana-Farber/Brigham and Women's Cancer Center (DF/BWCC), our many specialists manage your diagnosis as a team. Our gastroenterology, radiology, and pathology experts specialize in gastrointestinal cancer imaging and diagnostics. This gives us in-depth experience with the disease process and an extraordinary depth of knowledge.

    Radiology research

    Our radiologists are leading advanced research to develop better diagnostic tools to study cancer and determine how treatments affect the cancer.

    Our team regularly publishes its findings about the use of imaging for diagnosis, treatment response, and clinical management of cancer care.

    • Our team has published hundreds of articles on cancer imaging in the past three years.
    • We are investigating new approaches to cancer imaging, including dual energy CT. This research can optimize our understanding of this kind of cancer and help determine whether or not to operate.
    • We are studying the impact of new treatments such as immunotherapy and how best to image response to newer treatments.

    DF/BWCC pathologists review your pathology slides (even if an outside hospital already reviewed them) to make sure there is agreement on your exact diagnosis.

    • Our pathologists are leaders in the field of gastrointestinal cancer and have authored more than 500 original publications.
    • They work closely with our Center for Molecular Diagnostics and Center for Precision Cancer Medicine to get a complete picture of your tumor in order to direct the right therapy, based on both the tumor type and the molecular features of the cancer.

    Precision cancer medicine

    Clinicians at Dana-Farber/Brigham and Women's Cancer Center are now armed with specialized tests to create a precise "tumor profile" for each patient's cancer.

    If you have been diagnosed with colon cancer, it is important to be seen quickly to start timely treatment. We are committed to seeing patients for an initial diagnosis or second opinion within days, including next-day appointments in Boston. We will assemble the team of specialists that is right for your stage and type of colon cancer.

    Learn about the latest thinking in precision cancer medicine for colon cancer and explore a searchable database of clinical trials that focus on targeted therapies by disease, gene, and mutation.

    Staging

    The process used to find out the extent of the cancer within the colon, or if it has spread to other parts of the body, is called staging. This determines your prognosis and your treatment plan.

    There are three ways through which cancer can spread (metastasize) in the body: tissue, the lymph system, and the blood:

    • Tissue: The cancer spreads from where it began by growing into nearby areas.
    • Lymph system: The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
    • Blood: The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.

    Some staging can be done before having surgery, and other parts of the staging process are done after the cancer is removed from the colon. During your first meeting with your team at Dana-Farber/Brigham and Women's Cancer Center, we will discuss with you the best strategy to stage your cancer.

    Colon cancer can be assigned one of these stages:

    Stage 0 (Carcinoma in situ): Abnormal cells are present in a polyp, but have not invaded into the colon wall.

    Stage I: Cancer has spread from the innermost layer of the colon wall (submucosa) or the muscle layer, but there is no spread to lymph nodes or distant organs.

    stage I colon cancer illustration

    Stage II: Cancer has spread further into the colon wall than stage I, but there is no spread to lymph nodes or distant organs.

    • Stage IIA: Cancer has spread through the muscle layer of the colon wall to the serosa (the outside layer of the colon).

      stage II colon cancer illustration

    • Stage IIB: Cancer has spread through the outside layer, but not to organs.
    • Stage IIC: Cancer has spread through the outside layer to nearby organs.

    Stage III: Cancer has spread to lymph nodes near the colon, but not to distant organs.

    • Stage IIIA: Cancer may have spread through the mucosa (innermost layer of the colon wall) to the submucosa (the layer of tissue under the mucosa) or muscle layer, and has spread to one to three nearby lymph nodes or tissues near the lymph nodes. Or, cancer has spread through the mucosa to the submucosa and four to six nearby lymph nodes.

      stage IIIa colon cancer illustration

    • Stage IIIB: Cancer has spread through the muscle layer of the colon wall to the serosa or has spread through the serosa but not to nearby organs and one to three lymph nodes. Or, cancer has spread to the muscle layer or to the serosa, and to four to six nearby lymph nodes. Or, cancer has spread through the mucosa to the submucosa and may have spread to the muscle layer and has spread to seven or more nearby lymph nodes.

      stage IIIb colon cancer illustration

    • Stage IIIC: Cancer has spread through the serosa of the colon wall but not to nearby organs and four to six nearby lymph nodes. Or, cancer has spread through the muscle layer to the serosa or has spread through the serosa but not to nearby organs; cancer has spread to seven or more nearby lymph nodes. Or, cancer has spread through the serosa to nearby organs and to one or more nearby lymph nodes or to tissues near the lymph nodes.

      stage IIIc colon cancer illustration

    Stage IV: The cancer has spread to other parts of the body.

    • Stage IVA: Cancer has spread to one organ that is not near the colon, such as the liver, lung, or ovary, or to a distant lymph node. Cancer may have spread through the colon wall and to nearby organs or lymph nodes.
    • Stage IVB: Cancer has spread to more than one organ that is not near the colon or into the lining of the abdominal wall. Cancer may have spread through the colon wall and may have spread to nearby organs or lymph nodes.

    stage IV colon cancer illustration