This information is produced and provided by the National Cancer Institute (NCI). The information in this topic may have changed since it was written. For the most current information, contact the National Cancer Institute via the Internet web site at http://cancer.gov or call 1-800-4-CANCER.
The gastrointestinal (GI) tract is part of the digestive system, which processes nutrients (vitamins, minerals, carbohydrates, fats, proteins, and water) in foods that are eaten and helps pass waste material out of the body. The GI tract includes the stomach and intestines (bowels). The stomach is a J-shaped organ in the upper abdomen. Food moves from the throat to the stomach through a hollow, muscular tube called the esophagus. After leaving the stomach, partly-digested food passes into the small intestine and then into the large intestine (colon). The last 6 inches of the large intestine 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).
Anatomy of the lower digestive system, showing the colon and other organs.
GI complications are common in cancer patients. Complications are medical problems that occur during a disease, or after a procedure or treatment. They may be caused by the disease, procedure, or treatment, or may have other causes. This summary describes the following GI complications and their causes and treatments:
This summary is about GI complications in adults with cancer. Treatment of GI complications in children is different than treatment for adults.
With constipation, bowel movements are difficult or don't happen as often as usual.
Constipation is the slow movement of stool through the large intestine. The longer it takes for the stool to move through the large intestine, the more it loses fluid and the drier and harder it becomes. The patient may be unable to have a bowel movement, have to push harder to have a bowel movement, or have fewer than their usual number of bowel movements.
Certain medicines, changes in diet, not drinking enough fluids, and being less active are common causes of constipation.
Constipation is a common problem for cancer patients. Cancer patients may become constipated by any of the usual factors that cause constipation in healthy people. These include older age, changes in diet and fluid intake, and not getting enough exercise. In addition to these common causes of constipation, there are other causes in cancer patients.
Other causes of constipation include:
|Bowel movement habits|
|Conditions that prevent activity and exercise|
|Muscle and nerve disorders |
|Changes in body metabolism|
An assessment is done to help plan treatment.
The assessment includes a physical exam and questions about the patient's usual bowel movements and how they have changed.
The following tests and procedures may be done to help find the cause of the constipation:
There is no "normal" number of bowel movements for a cancer patient. Each person is different. You will be asked about bowel routines, food, and medicines:
For patients who have colostomies, care of the colostomy will be discussed.
Treating constipation is important to make the patient comfortable and to prevent more serious problems.
It's easier to prevent constipation than to relieve it. The health care team will work with the patient to prevent constipation. Patients who take opioids may need to start taking laxatives right away to prevent constipation.
Constipation can be very uncomfortable and cause distress. If left untreated, constipation may lead to fecal impaction. This is a serious condition in which stool will not pass out of the colon or rectum. It's important to treat constipation to prevent fecal impaction.
Prevention and treatment are not the same for every patient. Do the following to prevent and treat constipation:
When constipation is caused by opioids, treatment may be drugs that stop the effects of the opioids or other medicines, stool softeners, enemas, and/or manual removal of stool.
Fecal impaction is a mass of dry, hard stool that will not pass out of the colon or rectum.
Fecal impaction is dry stool that cannot pass out of the body. Patients with fecal impaction may not have gastrointestinal (GI) symptoms. Instead, they may have problems with circulation, the heart, or breathing. If fecal impaction is not treated, it can get worse and cause death.
A common cause of fecal impaction is using laxatives too often.
Repeated use of laxatives in higher and higher doses makes the colon less able to respond naturally to the need to have a bowel movement. This is a common reason for fecal impaction. Other causes include:
Certain types of mental illness may lead to fecal impaction.
Symptoms of fecal impaction include being unable to have a bowel movement and pain in the abdomen or back.
The following may be symptoms of fecal impaction:
These symptoms should be reported to the health care provider.
Assessment includes a physical exam and questions like those asked in the assessment of constipation.
The doctor will ask questions similar to those for the assessment of constipation:
The doctor will do a physical exam to find out if the patient has a fecal impaction. The following tests and procedures may be done:
A fecal impaction is usually treated with an enema.
The main treatment for impaction is to moisten and soften the stool so it can be removed or passed out of the body. This is usually done with an enema. Enemas are given only as prescribed by the doctor since too many enemas can damage the intestine. Stool softeners or glycerin suppositories may be given to make the stool softer and easier to pass. Some patients may need to have stool manually removed from the rectum after it is softened.
Laxatives that cause the stool to move are not used because they can also damage the intestine.
A bowel obstruction is a blockage of the small or large intestine by something other than fecal impaction.
Bowel obstructions (blockages) keep the stool from moving through the small or large intestines. They may be caused by a physical change or by conditions that stop the intestinal muscles from moving normally. The intestine may be partly or completely blocked. Most obstructions occur in the small intestine.
If the intestine is blocked by physical causes, it may decrease blood flow to blocked parts. Blood flow needs to be corrected or the affected tissue may die.
Conditions that affect the intestinal muscle
The most common cancers that cause bowel obstructions are cancers of the colon, stomach, and ovary.
Other cancers, such as lung and breast cancers and melanoma, can spread to the abdomen and cause bowel obstruction. Patients who have had surgery on the abdomen or radiation therapy to the abdomen have a higher risk of a bowel obstruction. Bowel obstructions are most common during the advanced stages of cancer.
Assessment includes a physical exam and imaging tests.
The following tests and procedures may be done to diagnose a bowel obstruction:
Treatment is different for acute and chronic bowel obstructions.
Acute bowel obstruction
Acute bowel obstructions occur suddenly, may have not occurred before, and are not long-lasting. Treatment may include the following:
Patients with symptoms that keep getting worse will have follow-up exams to check for signs and symptoms of shock and to make sure the obstruction isn't getting worse.
Chronic, malignant bowel obstruction
Chronic bowel obstructions keep getting worse over time. Patients who have advanced cancer may have chronic bowel obstructions that cannot be removed with surgery. The intestine may be blocked or narrowed in more than one place or the tumor may be too large to remove completely. Treatments include the following:
Diarrhea is frequent, loose, and watery bowel movements.
Diarrhea is frequent, loose, and watery bowel movements. Acute diarrhea lasts more than 4 days but less than 2 weeks. Symptoms of acute diarrhea may be loose stools and passing more than 3 unformed stools in one day. Diarrhea is chronic (long-term) when it goes on for longer than 2 months.
Diarrhea can occur at any time during cancer treatment. It can be physically and emotionally stressful for patients who have cancer.
In cancer patients, the most common cause of diarrhea is cancer treatment.
Causes of diarrhea in cancer patients include the following:
Assessment includes a physical exam, lab tests, and questions about diet and bowel movements.
Because diarrhea can be life-threatening, it is important to find out the cause so treatment can begin as soon as possible. The doctor may ask the following questions to help plan treatment:
Tests and procedures may include the following:
Treatment of diarrhea depends on what is causing it.
Treatment depends on the cause of the diarrhea. The doctor may make changes in medicines, diet, and/or fluids.
Radiation enteritis is inflammation of the intestine caused by radiation therapy.
Radiation enteritis is a condition in which the lining of the intestine becomes swollen and inflamed during or after radiation therapy to the abdomen, pelvis, or rectum. The small and large intestine are very sensitive to radiation. The larger the dose of radiation, the more damage may be done to normal tissue. Most tumors in the abdomen and pelvis need large doses of radiation. Almost all patients receiving radiation to the abdomen, pelvis, or rectum will have enteritis.
Radiation therapy to kill cancer cells in the abdomen and pelvis affects normal cells in the lining of the intestines. Radiation therapy stops the growth of cancer cells and other fast-growing cells. Since normal cells in the lining of the intestines grow quickly, radiation treatment to that area can stop those cells from growing. This makes it hard for tissue to repair itself. As cells die and are not replaced, gastrointestinal problems occur over the next few days and weeks.
Doctors are studying whether the order that radiation therapy, chemotherapy, and surgery are given affects how severe the enteritis will be.
Symptoms may begin during radiation therapy or months to years later.
Radiation enteritis may be acute or chronic:
The total dose of radiation and other factors affect the risk of radiation enteritis.
Only 5% to 15% of patients treated with radiation to the abdomen will have chronic problems. The amount of time the enteritis lasts and how severe it is depend on the following:
Acute and chronic enteritis have symptoms that are a lot alike.
Patients with acute enteritis may have the following symptoms:
Symptoms of acute enteritis usually go away 2 to 3 weeks after treatment ends.
Symptoms of chronic enteritis usually appear 6 to 18 months after radiation therapy ends. It can be hard to diagnose. The doctor will first check to see if the symptoms are being caused by a recurrent tumor in the small intestine. The doctor will also need to know the patient's full history of radiation treatments.
Patients with chronic enteritis may have the following signs and symptoms:
Assessment of radiation enteritis includes a physical exam and questions for the patient.
Patients will be given a physical exam and be asked questions about the following:
Treatment depends on whether the radiation enteritis is acute or chronic.
Acute radiation enteritis
Treatment of acute enteritis includes treating the symptoms. The symptoms usually get better with treatment, but if symptoms get worse, then cancer treatment may have to be stopped for a while.
Treatment of acute radiation enteritis may include the following:
Chronic radiation enteritis
Treatment of chronic radiation enteritis may include the following:
Check NCI's list of cancer clinical trials for U.S. supportive and palliative care trials about constipation, impaction, and bowel obstruction and diarrhea that are now accepting participants. The list of trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site.
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.
If you have questions or comments about this summary, please send them to Cancer.gov through the Web site's Contact Form. We can respond only to email messages written in English.
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.
The NCI's LiveHelp® 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|
|6116 Executive Boulevard, MSC8322|
|Bethesda, MD 20892-8322|
Search the NCI Web site
The NCI Web site 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.
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. These materials can also be ordered by telephone from the Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237).
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. 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.
Images in the PDQ summaries are used with permission of the author(s), artist, and/or publisher for use within the PDQ summaries only. Permission to use images outside the context of PDQ information must be obtained from the owner(s) and cannot be granted by the National Cancer Institute. Information about using the illustrations in the PDQ summaries, along with many other cancer-related images, are available in Visuals Online, a collection of over 2,000 scientific images.
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 method of treating symptoms 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. Some patients have symptoms caused by cancer treatment or by the cancer itself. During supportive care clinical trials, information is collected about how well new ways to treat symptoms of cancer work. The trials also study side effects of treatment and problems that come up during or after treatment. If a clinical trial shows that a new treatment is better than one currently being used, the new treatment may become "standard." Patients who have symptoms related to cancer treatment may want to think about taking part in a clinical trial.
Listings of clinical trials are included in PDQ and are available online at NCI's Web site. 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).
Last Revised: 2013-01-24
If you want to know more about cancer and how it is treated, or if you wish to know about clinical trials for your type of cancer, you can call the NCI's Cancer Information Service at 1-800-422-6237, toll free. A trained information specialist can talk with you and answer your questions.
Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.