Questions About Cancer? 1-800-4-CANCER

Rectal Cancer Treatment (PDQ®)

Patient Version
Last Modified: 03/16/2012

General Information About Rectal Cancer

Key Points for This Section


Rectal cancer is a disease in which malignant (cancer) cells form in the tissues of the rectum.

The rectum is part of the body’s digestive system. The digestive system removes and processes nutrients (vitamins, minerals, carbohydrates, fats, proteins, and water) from foods and helps pass waste material out of the body. The digestive system is made up of the esophagus, stomach, and the small and large intestines. The first 6 feet of the large intestine are called the large bowel or colon. The last 6 inches are the rectum and the anal canal. The anal canal ends at the anus (the opening of the large intestine to the outside of the body).

Enlarge 1
Gastrointestinal (digestive) system anatomy; shows esophagus, liver, stomach, colon, small intestine, rectum, and anus. 1
Anatomy of the lower digestive system, showing the colon and other organs.


See the following PDQ summaries for more information about rectal cancer:

Age and family history can affect the risk of developing rectal cancer.

Anything that increases your chance of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn’t mean that you will not get cancer. People who think they may be at risk should discuss this with their doctor. The following are possible risk factors for rectal cancer:

Possible signs of rectal cancer include a change in bowel habits or blood in the stool.

These and other symptoms may be caused by rectal cancer. Other conditions may cause the same symptoms. A doctor should be consulted if any of the following problems occur:

  • A change in bowel habits.
    • Diarrhea.
    • Constipation.
    • Feeling that the bowel does not empty completely.
    • Stools that are narrower or have a different shape than usual.
  • Blood (either bright red or very dark) in the stool.
  • General abdominal discomfort (frequent gas pains, bloating, fullness, or cramps).
  • Change in appetite.
  • Weight loss for no known reason.
  • Feeling very tired.

Tests that examine the rectum and colon are used to detect (find) and diagnose rectal cancer.

Tests used to diagnose rectal cancer include the following:

  • Physical exam and history: 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 will also be taken.
  • Digital rectal exam (DRE): An exam of the rectum. The doctor or nurse inserts a lubricated, gloved finger into the lower part of the rectum to feel for lumps or anything else that seems unusual. In women, the vagina may also be examined.
  • Proctoscopy: An exam of the rectum using a proctoscope, inserted into the rectum. A proctoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease.
  • Colonoscopy: A procedure to look inside the rectum and colon for polyps (small pieces of bulging tissue), abnormal areas, or cancer. A colonoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove polyps or tissue samples, which are checked under a microscope for signs of cancer.
    Enlarge 7
    Colonoscopy; shows colonoscope inserted through the anus and rectum and into the colon.  Inset shows patient on table having a colonoscopy. 7
    Colonoscopy. A thin, lighted tube is inserted through the anus and rectum and into the colon to look for abnormal areas.
  • Biopsy: The removal of cells or tissues so they can be viewed under a microscope to check for signs of cancer. Tumor tissue that is removed during the biopsy may be checked to see if the patient is likely to have the gene mutation that causes HNPCC. This may help to plan treatment. The following tests may be used:
  • 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 rectal cancer or other conditions

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis (chance of recovery) and treatment options depend on the following:

  • The stage of the cancer (whether it affects the inner lining of the rectum only, involves the whole rectum, or has spread to lymph nodes, nearby organs, or other places in the body).
  • Whether the tumor has spread into or through the bowel wall.
  • Where the cancer is found in the rectum.
  • Whether the bowel is blocked or has a hole in it.
  • Whether all of the tumor can be removed by surgery.
  • The patient’s general health.
  • Whether the cancer has just been diagnosed or has recurred (come back).

Stages of Rectal Cancer

Key Points for This Section


After rectal cancer has been diagnosed, tests are done to find out if cancer cells have spread within the rectum or to other parts of the body.

The process used to find out whether cancer has spread within the rectum or to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease. It is important to know the stage in order to plan treatment. The following tests and procedures may be used in the staging process:

  • 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, such as the abdomen, pelvis, or chest, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
  • MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).
  • Endoscopic ultrasound (EUS): A procedure in which an endoscope or rigid probe is inserted into the body through the rectum. The endoscope or probe has a light and a lens for viewing. A device at the end is used to bounce high-energy sound waves (ultrasound) off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram. This procedure is also called endosonography.
  • PET scan (positron emission tomography scan): A procedure to find malignant tumor cells in the body. A small amount of radioactive 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 picture because they are more active and take up more glucose than normal cells do.
  • 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 rectal cancer or other conditions.

There are three ways that cancer spreads in the body.

The three ways that cancer spreads in the body are:

  • Through tissue. Cancer invades the surrounding normal tissue.
  • Through the lymph system. Cancer invades the lymph system and travels through the lymph vessels to other places in the body.
  • Through the blood. Cancer invades the veins and capillaries and travels through the blood to other places in the body.

When cancer cells break away from the primary (original) tumor and travel through the lymph or blood to other places in the body, another (secondary) tumor may form. This process is called metastasis. The secondary (metastatic) tumor is the same type of cancer as the primary tumor. For example, if breast cancer spreads to the bones, the cancer cells in the bones are actually breast cancer cells. The disease is metastatic breast cancer, not bone cancer.

The following stages are used for rectal cancer:

Stage 0 (Carcinoma in Situ)

Enlarge 8
Stage 0 colon/rectal carcinoma in situ; shows a cross-section of the colon/rectum. An inset shows the layers of the colon/rectum wall with abnormal cells in the mucosa layer. Also shown are the submucosa, muscle layers, serosa, a blood vessel, and lymph nodes. 8
Stage 0 (rectal carcinoma in situ). Abnormal cells are shown in the mucosa of the rectum wall.

In stage 0, abnormal cells are found in the mucosa (innermost layer) of the rectum wall. These abnormal cells may become cancer and spread. Stage 0 is also called carcinoma in situ.

Stage I

Enlarge 9
Stage I colorectal cancer; shows a cross-section of the colon/rectum. An inset shows the layers of the colon/rectum wall with cancer in the mucosa, submucosa, and muscle layers. Also shown are the serosa, a blood vessel, and lymph nodes. 9
Stage I rectal cancer. Cancer has spread from the mucosa of the rectum wall to the muscle layer.

In stage I, cancer has formed in the mucosa (innermost layer) of the rectum wall and has spread to the submucosa (layer of tissue under the mucosa). Cancer may have spread to the muscle layer of the rectum wall.

Stage II

Enlarge 10
Stage II colorectal cancer; shows a cross-section of the colon/rectum and a three-panel inset. Each panel shows the layers of the colon/rectum wall: mucosa, submucosa, muscle layers, and serosa. Also shown are a blood vessel and lymph nodes. First panel shows stage IIA with cancer in the mucosa, submucosa, muscle layers, and serosa. Second panel shows stage IIB with cancer in all layers and spreading through the serosa. Third panel shows stage IIC with cancer spreading to nearby organs. 10
Stage II rectal cancer. In stage IIA, cancer has spread through the muscle layer of the rectum wall to the serosa. In stage IIB, cancer has spread through the serosa but has not spread to nearby organs. In stage IIC, cancer has spread through the serosa to nearby organs.

Stage II rectal cancer is divided into stage IIA, stage IIB, and stage IIC.

  • Stage IIA: Cancer has spread through the muscle layer of the rectum wall to the serosa (outermost layer) of the rectum wall.
  • Stage IIB: Cancer has spread through the serosa (outermost layer) of the rectum wall but has not spread to nearby organs.
  • Stage IIC: Cancer has spread through the serosa (outermost layer) of the rectum wall to nearby organs.

Stage III

Stage III rectal cancer is divided into stage IIIA, stage IIIB, and stage IIIC.

Enlarge 11
Stage IIIA colorectal cancer; shows a cross-section of the colon/rectum and a two-panel inset. Each panel shows the layers of the colon/rectum wall: mucosa, submucosa, muscle layers, and serosa. Also shown are a blood vessel and lymph nodes. First panel shows cancer in the mucosa, submucosa, muscle layers, and 2 lymph nodes. Second panel  shows cancer in the mucosa, submucosa, and 5 lymph nodes. 11
Stage IIIA rectal cancer. Cancer may have spread through the mucosa of the rectum wall to the submucosa and 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.

In stage IIIA:

  • Cancer may have spread through the mucosa (innermost layer) of the rectum wall to the submucosa (layer of tissue under the mucosa) and may have spread to the muscle layer of the rectum wall. Cancer has spread to at least one but not more than 3 nearby lymph nodes or cancer cells have formed in tissues near the lymph nodes; or
  • Cancer has spread through the mucosa (innermost layer) of the rectum wall to the submucosa (layer of tissue under the mucosa). Cancer has spread to at least 4 but not more than 6 nearby lymph nodes.
Enlarge 12
Stage IIIB colorectal cancer; shows a cross-section of the colon/rectum and a two-panel inset. Each panel shows the layers of the colon/rectum wall: mucosa, submucosa, muscle layers, and serosa. Also shown are a blood vessel and lymph nodes. First panel shows cancer in all layers, spreading through the serosa, and in 3 lymph nodes. Second panel shows cancer in all layers and in 5 lymph nodes. Third panel shows cancer in the mucosa, submucosa, muscle layers, and 7 lymph nodes. 12
Stage IIIB rectal cancer. Cancer has spread through the muscle layer of the rectum wall to the serosa or has spread through the serosa but not to nearby organs; cancer has spread to one to three nearby lymph nodes or to tissues near the 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; cancer has spread to seven or more nearby lymph nodes.

In stage IIIB:

  • Cancer has spread through the muscle layer of the rectum wall to the serosa (outermost layer) of the rectum wall or has spread through the serosa but not to nearby organs. Cancer has spread to at least one but not more than 3 nearby lymph nodes or cancer cells have formed in tissues near the lymph nodes; or
  • Cancer has spread to the muscle layer of the rectum wall or to the serosa (outermost layer) of the rectum wall. Cancer has spread to at least 4 but not more than 6 nearby lymph nodes; or
  • Cancer has spread through the mucosa (innermost layer) of the rectum wall to the submucosa (layer of tissue under the mucosa) and may have spread to the muscle layer of the rectum wall. Cancer has spread to 7 or more nearby lymph nodes.
Enlarge 13
Stage IIIC colorectal cancer; shows a cross-section of the colon/rectum wall and a three-panel inset. Each panel shows the layers of the colon/rectum wall: mucosa, submucosa, muscle layers, and serosa. Also shown are a blood vessel and lymph nodes. First panel shows cancer in all layers, spreading through the serosa, and in 4 lymph nodes. Second panel shows cancer in all layers and in 7 lymph nodes. Third panel shows cancer in all layers, spreading through the serosa, in 2 lymph nodes, and spreading to nearby organs. 13
Stage IIIC rectal cancer. Cancer has spread through the serosa of the rectum wall but not to nearby organs; cancer has spread to 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.

In stage IIIC:

  • Cancer has spread through the serosa (outermost layer) of the rectum wall but has not spread to nearby organs. Cancer has spread to at least 4 but not more than 6 nearby lymph nodes; or
  • Cancer has spread through the muscle layer of the rectum wall to the serosa (outermost layer) of the rectum wall or has spread through the serosa but has not spread to nearby organs. Cancer has spread to 7 or more nearby lymph nodes; or
  • Cancer has spread through the serosa (outermost layer) of the rectum wall and has spread to nearby organs. Cancer has spread to one or more nearby lymph nodes or cancer cells have formed in tissues near the lymph nodes.

Stage IV

Stage IV rectal cancer is divided into stage IVA and stage IVB.

Enlarge 14
Stage IV rectal cancer; drawing shows other parts of the body where rectal cancer may spread, including lymph nodes, lung, liver, abdominal wall, and ovary. Inset shows cancer spreading through the blood and lymph nodes to other parts of the body. 14
Stage IV rectal cancer. The cancer has spread through the blood and lymph nodes to other parts of the body, such as the lung, liver, abdominal wall, or ovary.
  • Stage IVA: Cancer may have spread through the rectum wall and may have spread to nearby organs or lymph nodes. Cancer has spread to one organ that is not near the rectum, such as the liver, lung, or ovary, or to a distant lymph node.
  • Stage IVB: Cancer may have spread through the rectum wall and may have spread to nearby organs or lymph nodes. Cancer has spread to more than one organ that is not near the rectum or into the lining of the abdominal wall.

Recurrent Rectal Cancer

Recurrent rectal cancer is cancer that has recurred (come back) after it has been treated. The cancer may come back in the rectum or in other parts of the body, such as the colon, pelvis, liver, or lungs.

Treatment Option Overview

Key Points for This Section


There are different types of treatment for patients with rectal cancer.

Different types of treatment are available for patients with rectal cancer. Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment. Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.

Four types of standard treatment are used:

Surgery

Surgery is the most common treatment for all stages of rectal cancer. The cancer is removed using one of the following types of surgery:

  • Polypectomy: If the cancer is found in a polyp (a small piece of bulging tissue), the polyp is often removed during a colonoscopy.
  • Local excision: If the cancer is found on the inside surface of the rectum and has not spread into the wall of the rectum, the cancer and a small amount of surrounding healthy tissue is removed.
  • Resection: If the cancer has spread into the wall of the rectum, the section of the rectum with cancer and nearby healthy tissue is removed. Sometimes the tissue between the rectum and the abdominal wall is also removed. The lymph nodes near the rectum are removed and checked under a microscope for signs of cancer.
  • Pelvic exenteration: If the cancer has spread to other organs near the rectum, the lower colon, rectum, and bladder are removed. In women, the cervix, vagina, ovaries, and nearby lymph nodes may be removed. In men, the prostate may be removed. Artificial openings (stoma) are made for urine and stool to flow from the body to a collection bag.

After the cancer is removed, the surgeon will either:

  • do an anastomosis (sew the healthy parts of the rectum together, sew the remaining rectum to the colon, or sew the colon to the anus);
    Enlarge 15
    Three-panel drawing showing rectal cancer surgery with anastomosis; first panel shows area of rectum with cancer, middle panel shows cancer and nearby tissue removed, last panel shows the colon and anus joined. 15
    Rectal cancer surgery with anastomosis. The rectum and part of the colon are removed, and then the colon and anus are joined.
    or
  • make a stoma (an opening) from the rectum to the outside of the body for waste to pass through. This procedure is done if the cancer is too close to the anus and is called a colostomy. A bag is placed around the stoma to collect the waste. Sometimes the colostomy is needed only until the rectum has healed, and then it can be reversed. If the entire rectum is removed, however, the colostomy may be permanent.

Radiation therapy or chemotherapy may be given before surgery to shrink the tumor, make it easier to remove the cancer, and lessen problems with bowel control after surgery. Treatment given before surgery is called neoadjuvant therapy. Even if all the cancer that can be seen at the time of the operation is removed, some patients may be given radiation therapy or chemotherapy after surgery to kill any cancer cells that are left. Treatment given after the surgery, to lower the risk that the cancer will come back, is called adjuvant therapy.

Radiation therapy

Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. The way the radiation therapy is given depends on the type and stage of the cancer being treated.

Chemotherapy

Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping the cells from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly in the cerebrospinal fluid, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy). The way the chemotherapy is given depends on the type and stage of the cancer being treated.

See Drugs Approved for Rectal Cancer 16 for more information.

Targeted therapy

Targeted therapy is a type of treatment that uses drugs or other substances to identify and attack specific cancer cells without harming normal cells. Monoclonal antibody therapy is a type of targeted therapy being used for the treatment of rectal cancer.

Monoclonal antibody therapy uses antibodies made in the laboratory from a single type of immune system cell. These antibodies can identify substances on cancer cells or normal substances that may help cancer cells grow. The antibodies attach to the substances and kill the cancer cells, block their growth, or keep them from spreading. Monoclonal antibodies are given by infusion. They may be used alone or to carry drugs, toxins, or radioactive material directly to cancer cells.

See Drugs Approved for Rectal Cancer 16 for more information.

Other types of treatment are being tested in clinical trials.

Information about clinical trials is available from the NCI Web site 17.

Patients may want to think about taking part in a clinical trial.

For some patients, taking part in a clinical trial may be the best treatment choice. Clinical trials are part of the cancer research process. Clinical trials are done to find out if new cancer treatments are safe and effective or better than the standard treatment.

Many of today's standard treatments for cancer are based on earlier clinical trials. Patients who take part in a clinical trial may receive the standard treatment or be among the first to receive a new treatment.

Patients who take part in clinical trials also help improve the way cancer will be treated in the future. Even when clinical trials do not lead to effective new treatments, they often answer important questions and help move research forward.

Patients can enter clinical trials before, during, or after starting their cancer treatment.

Some clinical trials only include patients who have not yet received treatment. Other trials test treatments for patients whose cancer has not gotten better. There are also clinical trials that test new ways to stop cancer from recurring (coming back) or reduce the side effects of cancer treatment.

Clinical trials are taking place in many parts of the country. See the Treatment Options section that follows for links to current treatment clinical trials. These have been retrieved from NCI's listing of clinical trials.

Follow-up tests may be needed.

Some of the tests that were done to diagnose the cancer or to find out the stage of the cancer may be repeated. Some tests will be repeated in order to see how well the treatment is working. Decisions about whether to continue, change, or stop treatment may be based on the results of these tests. This is sometimes called re-staging.

Some of the tests will continue to be done from time to time after treatment has ended. The results of these tests can show if your condition has changed or if the cancer has recurred (come back). These tests are sometimes called follow-up tests or check-ups.

After treatment for rectal cancer, a blood test to measure amounts of carcinoembryonic antigen (a substance in the blood that may be increased when cancer is present) may be done to see if the cancer has come back.

Treatment Options by Stage

A link to a list of current clinical trials is included for each treatment section. For some types or stages of cancer, there may not be any trials listed. Check with your doctor for clinical trials that are not listed here but may be right for you.

Stage 0 (Carcinoma in Situ)

Treatment of stage 0 may include the following:

Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with stage 0 rectal cancer 18. For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. General information about clinical trials is available from the NCI Web site 19.

Stage I Rectal Cancer

Treatment of stage I rectal cancer may include the following:

Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with stage I rectal cancer 20. For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. General information about clinical trials is available from the NCI Web site 19.

Stage II Rectal Cancer

Treatment of stage II rectal cancer may include the following:

Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with stage II rectal cancer 21. For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. General information about clinical trials is available from the NCI Web site 19.

Stage III Rectal Cancer

Treatment of stage III rectal cancer may include the following:

Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with stage III rectal cancer 22. For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. General information about clinical trials is available from the NCI Web site 19.

Stage IV and Recurrent Rectal Cancer

Treatment of stage IV and recurrent rectal cancer may include the following:

Treatment of rectal cancer that has spread to other organs depends on which organ the cancer has spread to.

  • Treatment for areas of cancer that have spread to the liver includes the following:
  • Treatment for areas of cancer that has spread to the lung or ovaries is surgery.

Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with stage IV rectal cancer 23 and recurrent rectal cancer 24. For more specific results, refine the search by using other search features, such as the location of the trial, the type of treatment, or the name of the drug. General information about clinical trials is available from the NCI Web site 19.

Changes to This Summary (03/16/2012)

The PDQ cancer information summaries are reviewed regularly and updated as new information becomes available. This section describes the latest changes made to this summary as of the date above.

Editorial changes were made to this summary.

Get More Information From NCI

Call 1-800-4-CANCER

For more information, U.S. residents may call the National Cancer Institute's (NCI's) Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237) Monday through Friday from 8:00 a.m. to 8:00 p.m., Eastern Time. A trained Cancer Information Specialist is available to answer your questions.

Chat online

The NCI's LiveHelp® 40 online chat service provides Internet users with the ability to chat online with an Information Specialist. The service is available from 8:00 a.m. to 11:00 p.m. Eastern time, Monday through Friday. Information Specialists can help Internet users find information on NCI Web sites and answer questions about cancer.

Write to us

For more information from the NCI, please write to this address:

NCI Public Inquiries Office
Suite 3036A
6116 Executive Boulevard, MSC8322
Bethesda, MD 20892-8322

Search the NCI Web site

The NCI Web site 41 provides online access to information on cancer, clinical trials, and other Web sites and organizations that offer support and resources for cancer patients and their families. For a quick search, use the search box in the upper right corner of each Web page. The results for a wide range of search terms will include a list of "Best Bets," editorially chosen Web pages that are most closely related to the search term entered.

There are also many other places to get materials and information about cancer treatment and services. Hospitals in your area may have information about local and regional agencies that have information on finances, getting to and from treatment, receiving care at home, and dealing with problems related to cancer treatment.

Find Publications

The NCI has booklets and other materials for patients, health professionals, and the public. These publications discuss types of cancer, methods of cancer treatment, coping with cancer, and clinical trials. Some publications provide information on tests for cancer, cancer causes and prevention, cancer statistics, and NCI research activities. NCI materials on these and other topics may be ordered online or printed directly from the NCI Publications Locator 42. These materials can also be ordered by telephone from the Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237).

About PDQ

PDQ is a comprehensive cancer database available on NCI's Web site.

PDQ is the National Cancer Institute's (NCI's) comprehensive cancer information database. Most of the information contained in PDQ is available online at NCI's Web site 41. PDQ is provided as a service of the NCI. The NCI is part of the National Institutes of Health, the federal government's focal point for biomedical research.

PDQ contains cancer information summaries.

The PDQ database contains summaries of the latest published information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries are available in two versions. The health professional versions provide detailed information written in technical language. The patient versions are written in easy-to-understand, nontechnical language. Both versions provide current and accurate cancer information.

The PDQ cancer information summaries are developed by cancer experts and reviewed regularly.

Editorial Boards made up of experts in oncology and related specialties are responsible for writing and maintaining the cancer information summaries. The summaries are reviewed regularly and changes are made as new information becomes available. The date on each summary ("Date Last Modified") indicates the time of the most recent change.

PDQ also contains information on clinical trials.

A clinical trial is a study to answer a scientific question, such as whether one treatment is better than another. Trials are based on past studies and what has been learned in the laboratory. Each trial answers certain scientific questions in order to find new and better ways to help cancer patients. During treatment clinical trials, information is collected about the effects of a new treatment and how well it works. If a clinical trial shows that a new treatment is better than one currently being used, the new treatment may become "standard." Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.

Listings of clinical trials are included in PDQ and are available online at NCI's Web site 19. Descriptions of the trials are available in health professional and patient versions. Many cancer doctors who take part in clinical trials are also listed in PDQ. For more information, call the Cancer Information Service 1-800-4-CANCER (1-800-422-6237).



Glossary Terms

abdominal (ab-DAH-mih-nul)
Having to do with the abdomen, which is the part of the body between the chest and the hips that contains the pancreas, stomach, intestines, liver, gallbladder, and other organs.
abnormal (ab-NOR-mul)
Not normal. An abnormal lesion or growth may be cancer, premalignant (likely to become cancer), or benign (not cancer).
anal (AY-nul)
Having to do with the anus. The anus is the opening of the rectum (last part of the large intestine) to the outside of the body.
antibody (AN-tee-BAH-dee)
A protein made by plasma cells (a type of white blood cell) in response to an antigen (a substance that causes the body to make a specific immune response). Each antibody can bind to only one specific antigen. The purpose of this binding is to help destroy the antigen. Some antibodies destroy antigens directly. Others make it easier for white blood cells to destroy the antigen.
antigen (AN-tih-jen)
Any substance that causes the body to make a specific immune response.
anus (AY-nus)
The opening of the rectum to the outside of the body.
appetite (A-peh-tite)
A desire to satisfy a physical or mental need, such as for food, sex, or adventure.
biopsy (BY-op-see)
The removal of cells or tissues for examination by a pathologist. The pathologist may study the tissue under a microscope or perform other tests on the cells or tissue. There are many different types of biopsy procedures. The most common types include: (1) incisional biopsy, in which only a sample of tissue is removed; (2) excisional biopsy, in which an entire lump or suspicious area is removed; and (3) needle biopsy, in which a sample of tissue or fluid is removed with a needle. When a wide needle is used, the procedure is called a core biopsy. When a thin needle is used, the procedure is called a fine-needle aspiration biopsy.
bloating (BLOH-ting)
A swelling or feeling of fullness in the abdomen. Bloating is usually the result of gas in the intestines and can be caused by many things, including overeating, lactose intolerance, and constipation. Bloating can also be a side effect of cancer or cancer treatment.
blood (blud)
A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.
bowel (BOW-ul)
The long, tube-shaped organ in the abdomen that completes the process of digestion. The bowel has two parts, the small bowel and the large bowel. Also called intestine.
breast (brest)
Glandular organ located on the chest. The breast is made up of connective tissue, fat, and breast tissue that contains the glands that can make milk. Also called mammary gland.
cancer (KAN-ser)
A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is a cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is a cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is a cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord. Also called malignancy.
carbohydrate (KAR-boh-HY-drayt)
A sugar molecule. Carbohydrates can be small and simple (for example, glucose) or they can be large and complex (for example, polysaccharides such as starch, chitin or cellulose).
CEA assay (... A-say)
A laboratory test that measures the level of carcinoembryonic antigen (CEA) in the blood. An increased amount of CEA may be found in the blood of people who have colon cancer or other types of cancer, certain other diseases, or who smoke. The amount of CEA in the blood may also help keep track of how well cancer treatments are working or if cancer has come back. CEA is a type of tumor marker. Also called carcinoembryonic antigen assay.
cell (sel)
The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.
chemical (KEH-mih-kul)
A substance made up of elements, such as hydrogen or sodium.
clinical trial (KLIH-nih-kul TRY-ul)
A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called clinical study.
colon (KOH-lun)
The longest part of the large intestine, which is a tube-like organ connected to the small intestine at one end and the anus at the other. The colon removes water and some nutrients and electrolytes from partially digested food. The remaining material, solid waste called stool, moves through the colon to the rectum and leaves the body through the anus.
colonoscope (koh-LAH-noh-SKOPE)
A thin, tube-like instrument used to examine the inside of the colon. A colonoscope has a light and a lens for viewing and may have a tool to remove tissue.
colonoscopy (KOH-luh-NOS-koh-pee)
Examination of the inside of the colon using a colonoscope, inserted into the rectum. A colonoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease.
colorectal cancer (KOH-loh-REK-tul KAN-ser)
Cancer that develops in the colon (the longest part of the large intestine) and/or the rectum (the last several inches of the large intestine before the anus).
condition (kun-DIH-shun)
In medicine, a health problem with certain characteristics or symptoms.
constipation (KON-stih-PAY-shun)
A condition in which stool becomes hard, dry, and difficult to pass, and bowel movements don’t happen very often. Other symptoms may include painful bowel movements, and feeling bloated, uncomfortable, and sluggish.
cramp (kramp)
A sharp pain that occurs when a muscle suddenly contracts (tightens up). Cramps commonly occur in the abdomen and legs.
diagnostic procedure (DY-ug-NAH-stik proh-SEE-jer)
A type of test used to help diagnose a disease or condition. Mammograms and colonoscopies are examples of diagnostic procedures. Also called diagnostic test.
diarrhea (dy-uh-REE-uh)
Frequent and watery bowel movements.
digestive system (dy-JES-tiv SIS-tem)
The organs that take in food and turn it into products that the body can use to stay healthy. Waste products the body cannot use leave the body through bowel movements. The digestive system includes the salivary glands, mouth, esophagus, stomach, liver, pancreas, gallbladder, small and large intestines, and rectum.
digital rectal examination (DIH-jih-tul REK-tul eg-ZA-mih-NAY-shun)
An examination in which a doctor inserts a lubricated, gloved finger into the rectum to feel for abnormalities. Also called DRE.
endometrium (en-doh-MEE-tree-um)
The layer of tissue that lines the uterus.
esophagus (ee-SAH-fuh-gus)
The muscular tube through which food passes from the throat to the stomach.
familial polyposis (fuh-MIH-lee-ul PAH-lee-POH-sis)
An inherited condition in which numerous polyps (growths that protrude from mucous membranes) form on the inside walls of the colon and rectum. It increases the risk of colorectal cancer. Also called familial adenomatous polyposis and FAP.
gene (jeen)
The functional and physical unit of heredity passed from parent to offspring. Genes are pieces of DNA, and most genes contain the information for making a specific protein.
hereditary (huh-REH-dih-tayr-ee)
Transmitted from parent to child by information contained in the genes.
hereditary nonpolyposis colon cancer (heh-REH-dih-TAYR-ee NON-PAH-lee-POH-sis KOH-lun KAN-ser)
An inherited disorder in which affected individuals have a higher-than-normal chance of developing colorectal cancer and certain other types of cancer, often before the age of 50. Also called HNPCC and Lynch syndrome.
immunohistochemistry (IH-myoo-noh-HIS-toh-KEH-mih-stree)
A technique used to identify specific molecules in different kinds of tissue. The tissue is treated with antibodies that bind the specific molecule. These are made visible under a microscope by using a color reaction, a radioisotope, colloidal gold, or a fluorescent dye. Immunohistochemistry is used to help diagnose diseases, such as cancer, and to detect the presence of microorganisms. It is also used in basic research to understand how cells grow and differentiate (become more specialized).
laboratory test (LA-bruh-tor-ee...)
A medical procedure that involves testing a sample of blood, urine, or other substance from the body. Tests can help determine a diagnosis, plan treatment, check to see if treatment is working, or monitor the disease over time.
large intestine (larj in-TES-tin)
The long, tube-like organ that is connected to the small intestine at one end and the anus at the other. The large intestine has four parts: cecum, colon, rectum, and anal canal. Partly digested food moves through the cecum into the colon, where water and some nutrients and electrolytes are removed. The remaining material, solid waste called stool, moves through the colon, is stored in the rectum, and leaves the body through the anal canal and anus.
lubricant (LOO-brih-kunt)
An oily or slippery substance.
lymph node (limf node)
A rounded mass of lymphatic tissue that is surrounded by a capsule of connective tissue. Lymph nodes filter lymph (lymphatic fluid), and they store lymphocytes (white blood cells). They are located along lymphatic vessels. Also called lymph gland.
medical history (MEH-dih-kul HIH-stuh-ree)
A record of information about a person’s health. A personal medical history may include information about allergies, illnesses, surgeries, immunizations, and results of physical exams and tests. It may also include information about medicines taken and health habits, such as diet and exercise. A family medical history includes health information about a person’s close family members (parents, grandparents, children, brothers, and sisters). This includes their current and past illnesses. A family medical history may show a pattern of certain diseases in a family.
microscope (MY-kroh-SKOPE)
An instrument that is used to look at cells and other small objects that cannot be seen with the eye alone.
mineral (MIH-neh-rul)
In medicine, a mineral is a nutrient that is needed in small amounts to keep the body healthy. Mineral nutrients include the elements calcium, magnesium, and iron.
mutation (myoo-TAY-shun)
Any change in the DNA of a cell. Mutations may be caused by mistakes during cell division, or they may be caused by exposure to DNA-damaging agents in the environment. Mutations can be harmful, beneficial, or have no effect. If they occur in cells that make eggs or sperm, they can be inherited; if mutations occur in other types of cells, they are not inherited. Certain mutations may lead to cancer or other diseases.
nurse (nurs)
A health professional trained to care for people who are ill or disabled.
nutrient (NOO-tree-ent)
A chemical compound (such as protein, fat, carbohydrate, vitamin, or mineral) contained in foods. These compounds are used by the body to function and grow.
organ (OR-gun)
A part of the body that performs a specific function. For example, the heart is an organ.
ovary (OH-vuh-ree)
One of a pair of female reproductive glands in which the ova, or eggs, are formed. The ovaries are located in the pelvis, one on each side of the uterus.
PDQ
PDQ is an online database developed and maintained by the National Cancer Institute. Designed to make the most current, credible, and accurate cancer information available to health professionals and the public, PDQ contains peer-reviewed summaries on cancer treatment, screening, prevention, genetics, complementary and alternative medicine, and supportive care; a registry of cancer clinical trials from around the world; and directories of physicians, professionals who provide genetics services, and organizations that provide cancer care. Most of this information, and more specific information about PDQ, can be found on the NCI's Web site at http://www.cancer.gov/cancertopics/pdq. Also called Physician Data Query.
personal history (PER-suh-nul HIH-stuh-ree)
A collection of information about a person’s health. It may include information about allergies, illnesses and surgeries, and dates and results of physical exams, tests, screenings, and immunizations. It may also include information about medicines taken and about diet and exercise. Also called personal health record and personal medical history.
physical examination (FIH-zih-kul eg-ZA-mih-NAY-shun)
An exam of the body to check for general signs of disease.
polymerase chain reaction (puh-LIH-meh-rays chayn ree-AK-shun)
A laboratory method used to make many copies of a specific DNA sequence. Also called PCR.
polyp (PAH-lip)
A growth that protrudes from a mucous membrane.
proctoscopy (prok-TOS-koh-pee)
Examination of the rectum using a proctoscope, inserted into the rectum. A proctoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease.
prognosis (prog-NO-sis)
The likely outcome or course of a disease; the chance of recovery or recurrence.
protein (PROH-teen)
A molecule made up of amino acids that are needed for the body to function properly. Proteins are the basis of body structures such as skin and hair and of substances such as enzymes, cytokines, and antibodies.
radioisotope (RAY-dee-oh-I-suh-tope)
An unstable form of a chemical element that releases radiation as it breaks down and becomes more stable. Radioisotopes may occur in nature or be made in a laboratory. In medicine, they are used in imaging tests and in treatment. Also called radionuclide.
recover (ree-KUH-ver)
To become well and healthy again.
rectal cancer (REK-tul KAN-ser)
Cancer that forms in the tissues of the rectum (the last several inches of the large intestine closest to the anus).
rectum (REK-tum)
The last several inches of the large intestine closest to the anus.
recur (ree-KER)
To come back or to return.
recurrent cancer (ree-KER-ent KAN-ser)
Cancer that has recurred (come back), usually after a period of time during which the cancer could not be detected. The cancer may come back to the same place as the original (primary) tumor or to another place in the body. Also called recurrence.
reverse transcription (ree-VERS tran-SKRIP-shun)
In biology, the process in cells by which an enzyme makes a copy of DNA from RNA. The enzyme that makes the DNA copy is called reverse transcriptase and is found in retroviruses, such as the human immunodeficiency virus (HIV). Reverse transcription can also be carried out in the laboratory.
risk factor (... FAK-ter)
Something that increases the chance of developing a disease. Some examples of risk factors for cancer are age, a family history of certain cancers, use of tobacco products, being exposed to radiation or certain chemicals, infection with certain viruses or bacteria, and certain genetic changes.
small intestine (... in-TES-tin)
The part of the digestive tract that is located between the stomach and the large intestine.
stage (stayj)
The extent of a cancer in the body. Staging is usually based on the size of the tumor, whether lymph nodes contain cancer, and whether the cancer has spread from the original site to other parts of the body.
stomach (STUH-muk)
An organ that is part of the digestive system. The stomach helps digest food by mixing it with digestive juices and churning it into a thin liquid.
stool (stool)
The material in a bowel movement. Stool is made up of undigested food, bacteria, mucus, and cells from the lining of the intestines. Also called feces.
surgery (SER-juh-ree)
A procedure to remove or repair a part of the body or to find out whether disease is present. An operation.
symptom (SIMP-tum)
An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.
tissue (TIH-shoo)
A group or layer of cells that work together to perform a specific function.
tumor (TOO-mer)
An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancer), or malignant (cancer). Also called neoplasm.
vagina (vuh-JY-nuh)
The muscular canal that goes from the uterus to the outside of the body. During birth, the baby passes through the vagina. Also called birth canal.
vitamin (VY-tuh-min)
A nutrient that the body needs in small amounts to function and stay healthy. Sources of vitamins are plant and animal food products and dietary supplements. Some vitamins are made in the human body from food products. Vitamins are either fat-soluble (can dissolve in fats and oils) or water-soluble (can dissolve in water). Excess fat-soluble vitamins are stored in the body’s fatty tissue, but excess water-soluble vitamins are removed in the urine. Examples are vitamin A, vitamin C, and vitamin E.

Table of Links

1http://www.cancer.gov/PublishedContent/MediaLinks/290421.html
2http://www.cancer.gov/cancertopics/pdq/treatment/gist/Patient
3http://www.cancer.gov/cancertopics/pdq/prevention/colorectal/Patient
4http://www.cancer.gov/cancertopics/pdq/screening/colorectal/Patient
5http://www.cancer.gov/cancertopics/pdq/genetics/colorectal/HealthProfessional
6http://www.cancer.gov/cancertopics/pdq/treatment/unusual-cancers-childhood/Pati
ent/Page5#Section_122
7http://www.cancer.gov/PublishedContent/MediaLinks/290422.html
8http://www.cancer.gov/PublishedContent/MediaLinks/290423.html
9http://www.cancer.gov/PublishedContent/MediaLinks/290424.html
10http://www.cancer.gov/PublishedContent/MediaLinks/290425.html
11http://www.cancer.gov/PublishedContent/MediaLinks/290426.html
12http://www.cancer.gov/PublishedContent/MediaLinks/290427.html
13http://www.cancer.gov/PublishedContent/MediaLinks/290428.html
14http://www.cancer.gov/PublishedContent/MediaLinks/290429.html
15http://www.cancer.gov/PublishedContent/MediaLinks/290430.html
16http://www.cancer.gov/cancertopics/druginfo/colorectalcancer#dal2
17http://cancer.gov/clinicaltrials
18http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?Diagnosis=43235&tt=1&a
mp;format=1&cn=1
19http://www.cancer.gov/clinicaltrials
20http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?Diagnosis=43286&tt=1&a
mp;format=1&cn=1
21http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?Diagnosis=43352&tt=1&a
mp;format=1&cn=1
22http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?Diagnosis=43420&tt=1&a
mp;format=1&cn=1
23http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?Diagnosis=43422&tt=1&a
mp;format=1&cn=1
24http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?Diagnosis=43429&tt=1&a
mp;format=1&cn=1
25http://www.cancer.gov/cancertopics/types/colon-and-rectal
26http://www.cancer.gov/cancertopics/wyntk/colon-and-rectal
27http://www.cancer.gov/cancertopics/factsheet/Detection/colorectal-screening
28http://www.cancer.gov/cancertopics/factsheet/Therapy/targeted
29http://www.cancer.gov/cancertopics/understandingcancer/targetedtherapies
30http://www.cancer.gov/cancertopics/UnderstandingCancer/genetesting
31http://www.cancer.gov/cancertopics/wyntk/overview
32http://www.cancer.gov/cancertopics/understandingcancer/cancer
33http://www.cancer.gov/cancertopics/factsheet/Detection/staging
34http://www.cancer.gov/cancertopics/chemotherapy-and-you
35http://www.cancer.gov/cancertopics/radiation-therapy-and-you
36http://www.cancer.gov/cancertopics/coping
37http://www.cancer.gov/cancertopics/cancerlibrary/questions
38http://www.cancer.gov/cancertopics/cancerlibrary
39http://dccps.cancer.gov/ocs/resources.html
40https://livehelp.cancer.gov
41http://cancer.gov
42https://pubs.cancer.gov/ncipl