Diagnosing Colon Cancer

About Colon Cancer

At Penn Medicine's Abramson Cancer Center, patients with colon cancer receive their care from a multidisciplinary team of nationally recognized experts in the diagnosis, treatment and research of gastrointestinal cancer.

The colon is the largest part of the large intestine, also known as the large bowel. After food is chewed and swallowed, it travels through the stomach and small intestine where it is broken down and most of the nutrients absorbed. It then passes to the large intestine where water and nutrients are absorbed from the food and waste matter is stored. The colon's function is to change liquid waste into solid waste and prepare it to be expelled from the body through the anus.

Colon cancer is the third most common type of cancer in both men and women, and is the second leading cause of death from cancer in the United States. Colon cancer is cancer that forms in the lining tissues of the colon. Most colon tumors begin when normal tissue forms a polyp, or pre-cancerous growth projecting from the wall of the colon. As the polyp grows, a tumor forms. Because the tumor grows slowly, early detection is possible through screening and tests.

Colon cancer is often combined with rectal cancer and can be referred to as “colorectal cancer.”

Penn Medicine's multidisciplinary approach to cancer diagnosis and treatment provides better outcomes and gives patients access to the most advanced treatment, surgical techniques and clinical trials.

Because navigating a cancer diagnosis and treatment options can be difficult, patients who wish to connect with a cancer specialist at Penn Medicine can speak with a cancer nurse, who can help them make an appointment with the right physician.

To connect with a cancer nurse at Penn Medicine, patients should call 800-789-PENN (7366).

Read more About Colon Cancer

Diagnosing Colon Cancer

An accurate cancer diagnosis from trusted cancer specialists is the first step in getting personalized treatment options to treat colon cancer.

Patients who choose Penn’s Abramson Cancer Center benefit from a multidisciplinary team of cancer specialists including gastroenterologists, radiologists, pathologists and surgeons who work together to provide a diagnosis and joined by radiation oncologists and medical oncologists to develop an appropriate treatment plan customized for each patient with colon cancer.

Cancer specialists at Penn Medicine are highly experienced in using the most advanced techniques for diagnosing colon cancer and are actively researching better and more precise ways to detect colon cancer.

Navigating a cancer diagnosis and treatment options can be difficult, patients who wish to connect with a cancer specialist at Penn Medicine can speak with a cancer nurse, who can help them make an appointment with the right person. Penn Medicine’s contact center has experienced cancer nurses available and ready to guide patients in finding the cancer specialist right for them.

To connect with a cancer nurse at Penn Medicine, patients should call 800-789-PENN (7366).


Screening for Colon Cancer

Colon cancer is usually slow to develop, so the chances are good for catching it early through regular screenings.

Most colon cancer is found through a colonoscopy. A colonoscopy is a procedure done under sedation. The physician places a thin, tube-like instrument with a light and a lens for viewing inside the rectum and colon. The scope may also have a tool to remove polyps or tissue samples that are checked for cancer in a lab.

The American Cancer Society recommends a colonoscopy every 10 years beginning at age 50 for people at average risk. People at high risk for colon and rectal cancer should talk with their physicians regarding recommendations for screening.

Diagnostic Tools for Colon Cancer

If physicians suspect colon cancer, they might perform or order one or more of these tests to diagnosis and stage colon cancer.

  • Medical history and physical exam. An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments is also taken.
  • Digital rectal exam. The anus and rectum are examined by the physician or nurse who inserts a lubricated, gloved finger into the lower part of the rectum to feel for lumps or anything else unusual.
  • Fecal occult blood test. This test examines stool samples for blood.
  • Imaging tests. Pictures of the inside of the body can help find out whether a suspicious area might be cancerous, to learn how far cancer may have spread, and to help determine if treatment is working.
    • Colonoscopy. Most rectal cancer is found through a colonoscopy. A colonoscopy is a procedure done under sedation.  The physician places a thin, tube-like instrument with a light and a lens for viewing inside the rectum and colon. The scope may also have a tool to remove polyps or tissue samples which are checked for cancer in a lab.
    • Barium enema. An enema containing barium, a silver-white metallic compound, is put into the rectum. The barium coats the lower part of the digestive tract and X-rays are taken. Also called a lower GI series.
    • Computed tomography (CT) scan. A CT scan creates a 3-D X-ray of the chest, abdomen and pelvis. A computer then combines these images into a detailed, cross-sectional view that shows any abnormalities or tumors. A CT scan is used to see if the tumor has spread to the liver and to detect a carcinoid tumor in lymph nodes behind the abdomen. Sometimes, a contrast medium (dye) is used to provide better detail.
    • Positron emission tomography (PET) scan. A PET scan is a way to create pictures of organs and tissues inside the body. A small amount of a radioactive substance is injected into a patient’s body. Tumors absorb the radioactive substance, and a scanner detects this substance to produce images.
    • Magnetic resonance imaging (MRI). Magnetic fields are used to create detailed images of the body. A contrast medium may be injected into a patient’s vein to create a clearer picture.
  • Biopsy. When other tests find a change that is possibly cancer, a sample of the suspicious area or lymph node is removed and viewed under a microscope. A biopsy is the only way to tell if cancer is really present.
  • Lab tests. A physician may order blood tests that measure the level of carcinoembryonic antigen (CEA) in the blood. CEA is released into the bloodstream by cancer and normal cells. When found in higher than normal amounts, it may be a sign of cancer. A complete blood count to assess the patient for anemia may also be ordered.
  • Genetic testing. Molecular genotyping is used for people at high risk for hereditary syndromes and diseases.

 

Staging Colon Cancer

Staging is a way of describing cancer: where it is located, if or where it has spread, and if it is affecting the functions of other organs in the body. Doctors use diagnostic tests to determine the cancer's stage, so staging may not be complete until all the tests are finished. Knowing the stage helps the doctor to decide what kind of treatment is best and can help predict a patient's chance of recovery.

The colon is made up of four layers:

  • The innermost layer, called the mucosa.
  • The next innermost layer, called the submucosa.
  • The muscle layer.
  • The outer layer called the serosa.

Knowing these layers can help patients understand how colon cancer is staged.

  • Stage 0. Abnormal cells are found only in the mucosa, also called carcinoma in situ.
  • Stage I. Cancer has formed in the mucosa and has spread to submucosa. Cancer may have spread to the muscle layer.
  • Stage II. One of the following:
    • IIA. Cancer has spread through the muscle layer of the colon to the serosa.
    • IIB. Cancer has spread through the serosa of the colon wall, but not to nearby organs.
    • IIC. Cancer has spread through the serosa of the colon wall to nearby organs.
  • Stage III. One of the following:
    • IIIA. Stage IIIA is subdivided into two more divisions.
      • Cancer may have spread through the mucosa of the colon wall to submucosa, and may have spread to the muscle layer. Cancer has spread to at least one, but no more than three nearby lymph nodes or cancer cells are found in tissues near lymph nodes.
      • Cancer has spread through the mucosa to the submucosa. Cancer has spread to at least four, but no more than six nearby lymph nodes.
    • IIIB. 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 at least one, but no more than three nearby lymph nodes or cancer cells have formed in tissue near the lymph nodes.
      • To the muscle layer of to the serosa. Cancer has spread to at least four, but no more than six lymph nodes.
      • Through the mucosa to the submucosa and may have spread to the muscle layer. Cancer has spread to seven or more lymph nodes.
    • IIIC. Cancer has spread:
      • Through the serosa but not to nearby organs. Cancer has spread to at least four, but no more than six nearby lymph nodes.
      • 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.
      • Through the serosa and to nearby organs. Cancer has spread to one ore more nearby lymph nodes or cancer cells have formed in tissues near lymph nodes.
  • Stage IV. Divided into IVA and IVB.
    • IVA. Cancer may have spread through the colon wall and to nearby organs or lymph nodes. Cancer has spread to one organ that is not near the colon, or to a distant lymph node.
    • IVB. Cancer may have spread through the colon wall and to nearby organs or lymph nodes. Cancer has spread to more than one organ that is not near the colon or into the lining of the abdominal wall.

Colon Cancer Treatment

Following the diagnosis and staging of colon cancer, cancer specialists at Penn Medicine’s Abramson Cancer Center develop a personalized treatment plan. Penn’s treatment options for colon cancer include:

  • Surgery
    • Segmented colon resection
    • Local excision
    • Resection of limited metastatic disease
  • Radiation therapy
    • 3-D conformal radiation
    • Intensity-modulated radiation therapy (IMRT)
    • Volumetric-modulated arc therapy (VMAT)
    • Proton therapy
  • Chemotherapy and biologic therapies
    • Chemotherapy (alone or combined with monoclonal antibody therapy)
    • Liver-directed therapies
    • Monoclonal antibody therapy
  • Clinical trials
  • Other treatments
    • Integrative medicine and wellness
    • Palliative care
    • Penn Home Care and Hospice

Because navigating a cancer diagnosis and treatment options can be difficult, patients who wish to connect with a cancer specialist at Penn Medicine can speak with a cancer nurse, who can help them make an appointment with the right person.

To connect with a cancer nurse at Penn Medicine, patients should call 1-800-789-PENN (7366).

Read more Colon Cancer Treatment

Colon Cancer Survivorship

Survivorship programs at Penn Medicine are a distinct phase of colon cancer care and are designed to help patients' transition from their cancer treatment routine to a post-cancer care lifestyle. There are more than 12 million cancer survivors living and thriving today as a result of advances in cancer treatment. However, cancer treatments can result in physical, emotional and financial complications long after the therapy is complete.

Read more Colon Cancer Survivorship


Suzi F. Garber

Suzi F. Garber, of Reading, PA., a neuroendocrine tumor patient at the Abramson Cancer Center, writes about her experience so that others might benefit from her story and become proactive advocates for themselves and their loved ones.

For ma

Stand Up to Cancer

Peter O'Dwyer, MD, professor of Hematology-Oncology and program director of Development Therapeutics in the Abramson Cancer Center, was interviewed on NBC10's 10! Show about Penn's work as part of the Stand Up to Cancer Dream Team... Read more

Clinical Trials

Colorectal Cancer Trials

Phase III Randomized Trial of the Role of Whole Brain Radiation Therapy in Addition to Radiosurgery... more