Introduction
Overview
Constipation

Description and Causes Assessment of Constipation Treatment

Impaction

Description and Causes Assessment of Impaction Treatment of Impaction

Bowel Obstruction

Description and Causes Assessment of Bowel Obstruction Treatment of Acute Bowel Obstruction Treatment of Chronic, Malignant Bowel Obstruction

Diarrhea

Causes Assessment Treatment

Radiation Enteritis

Causes and Symptoms Assessment of Radiation Enteritis Treatment of Acute Radiation Enteritis Treatment of Chronic Radiation Enteritis

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Changes to This Summary (07/19/2006)
Questions or Comments About This Summary
About PDQ

Introduction

This patient summary on gastrointestinal complications is adapted from a summary written for health professionals by cancer experts. This and other credible information about cancer treatment, screening, prevention, supportive care, and ongoing clinical trials, is available from the National Cancer Institute. Gastrointestinal complications such as constipation, impaction, bowel obstruction, diarrhea, and radiation enteritis are common problems for cancer patients, with causes that include the cancer itself or treatment of the cancer. This brief summary describes the differences between constipation, impaction, bowel obstruction, and diarrhea; their causes; and their treatment. Treatment of children is different from adults. The doctor will prescribe treatments according to the child's age and diagnosis.

Overview

Constipation is the slow movement of feces (stool or body wastes) through the large intestine resulting in infrequent bowel movements and the passage of dry, hard stools. The longer it takes for the stool to move through the large intestine, the more fluid is absorbed and the drier and harder the stool becomes.

Inactivity, immobility, or physical and social barriers (for example, bathrooms being unavailable or inconveniently located) can make constipation worse. Depression and anxiety caused by cancer treatment or cancer pain can also lead to constipation. The most common causes of constipation are not drinking enough fluids and taking pain medications.

Constipation is annoying and uncomfortable, but fecal impaction (a collection of dry, hard stool in the colon or rectum) can be life-threatening. Patients with a fecal impaction may not have gastrointestinal symptoms. Instead, they may have circulation, heart, or breathing problems. If fecal impaction is not recognized, the signs and symptoms will get worse and the patient could die.

A bowel obstruction is a partial or complete blockage of the small or large intestine by a process other than fecal impaction. Bowel obstructions are classified by the type of obstruction, how the obstruction occurred, and where it is. Tumors growing inside or outside the bowel, and scar tissue that develops after surgery, can affect bowel function and cause a partial or complete obstruction. Patients who have colostomies are especially at risk of developing constipation, which can lead to bowel obstruction.

Diarrhea can occur at any time during cancer treatment. Although diarrhea occurs less often than constipation, it can be physically and emotionally devastating for patients who have cancer. Diarrhea can cause:

• Changes in eating patterns.
• A loss of body fluids.
• Chemical imbalances in the blood.
• Impairments in physical function.
• Excessive tiredness.
• Skin problems.
• A decrease in physical activity.
• Problems that can be life-threatening in some patients.

Diarrhea is an abnormal increase in the amount of fluid in the stool that lasts more than 4 days but less than 2 weeks. It may also be described as an abnormal increase in the amount of fluid in the stool and the passage of more than 3 unformed stools during a 24-hour period. Diarrhea is considered a long-term problem when it lasts longer than 2 months.

Radiation enteritis is a condition in which the lining of the bowel becomes swollen and inflamed during or after radiation therapy to the abdomen, pelvis, or rectum. The large and small bowels are very sensitive to radiation. The larger the dose of radiation, the greater the damage to normal bowel tissue. Most tumors in the abdomen and pelvis need large doses, and almost all patients receiving radiation to the abdomen, pelvis, or rectum will show signs of acute enteritis.

Acute symptoms are those that appear during the first course of radiation therapy and up to 8 weeks later. Chronic radiation enteritis may appear months to years after radiation therapy is completed, or it may begin as acute enteritis and continue after treatment stops. Only 5% to 15% of persons treated with radiation to the abdomen will develop chronic problems. Several factors affect how long the enteritis will last and how severe it will be:

• The dose of radiation given.
• The tumor size and how much it has spread.
• The amount of normal bowel treated.
• Whether chemotherapy was given at the same time as the radiation therapy.
• Whether radiation implants were used.
• Whether the patient has high blood pressure, diabetes, pelvic inflammatory disease, or poor nutrition, or has had surgery to the abdomen or pelvis. These conditions can decrease blood flow to the bowel wall and affect bowel movement, increasing the chance of radiation injury.

Constipation

Description and Causes

Common factors that may cause constipation in healthy people are eating a low- fiber diet, postponing visits to the toilet, using laxatives and enemas excessively, not drinking enough fluids, and exercising too little. In persons with cancer, constipation may be a symptom of cancer, a result of a growing tumor, or a result of cancer treatment. Constipation may also be a side effect of medications for cancer or cancer pain and may be a result of other changes in the body (organ failure, decreased ability to move, and depression). Other causes of constipation include dehydration and not eating enough. Cancer, cancer treatment, aging, and declining health can contribute to causing constipation.

More specific causes of constipation that can result in bowel impaction include:

Diet

• Not including enough high-fiber foods in the diet.
• Not drinking enough water or other fluids.

Changed Bowel Habits

• Repeatedly ignoring the urge to pass stool.
• Using too many laxatives and enemas.

Immobility and Lack of Exercise

• Spinal cord injury, spinal cord compression, bone fractures, fatigue, weakness, long periods of bedrest.
• Inability to tolerate movement and exercise due to respiratory or cardiac problems.

Medications

• Chemotherapy treatments.
• Pain medications.
• Medications for anxiety and depression.
• Stomach antacids.
• Diuretics.
• Vitamin supplements such as iron and calcium.
• Sleep medications.
• General anesthesia.

Bowel Disorders

• Irritable colon.
• Diverticulitis.
• Tumor.

Muscle and Nerve Disorders (nerve damage can lead to loss of muscle tone in the bowel)

• Brain tumors.
• Spinal cord compression from a tumor or other spinal cord injury.
• Stroke or other disorders that cause muscle weakness or movement.
• Weakness of the diaphragm or abdominal muscles making it difficult to take a deep breath and push to have a bowel movement.

Body Metabolism Disorders

• Under-secretion of the thyroid gland.
• Increased level of calcium in the blood.
• Low levels of potassium or sodium in the blood.
• Diabetes with nerve dysfunction.

Environmental Factors

• Needing assistance to go to the bathroom.
• Being in unfamiliar surroundings or a hurried atmosphere.
• Living in extreme heat leading to dehydration.
• Needing to use a bedpan or bedside commode.
• Lack of privacy.

A medical history and physical examination can identify the causes of constipation. The examination may include a digital rectal exam (the doctor inserts a gloved, lubricated finger into the rectum to check for stool impaction) or a test for blood in the stool. If cancer is suspected, a thorough examination of the rectum and colon may be done with a lighted tube inserted through the anus and into the colon. The following questions may be asked:

• What is your normal bowel pattern? How often do you have a bowel movement? When and how much?



• When was your last bowel movement? What was it like (how much, hard or soft, color)? Was there any blood?



• Has your stomach hurt or have you had any cramping, nausea, vomiting, pain, gas, or feeling of fullness near the rectum?



• Do you use laxatives or enemas regularly? What do you normally do to relieve constipation? Does this usually work?



• What kind of food do you eat? How much and what type of fluids do you drink daily?



• What medicine are you taking? How much and how often?



• Is this constipation a recent change in your normal habits?



• How many times a day do you pass gas?

Treatment of constipation includes prevention (if possible), elimination of possible causes, and limited use of laxatives. Suggestions for the patient's treatment plan may include the following:

• Keep a record of all bowel movements.



• Increase the fluid intake by drinking eight 8- ounce glasses of fluid each day (patients who have kidney or heart disease may need to limit fluid intake).



• Exercise regularly, including abdominal exercises in bed or moving from the bed to chair if the patient cannot walk.



• Increase the amount of dietary fiber by eating more fruits (raisins, prunes, peaches, and apples), vegetables (squash, broccoli, carrots, and celery), and whole grain cereals, breads, and bran. Patients must drink more fluids when increasing dietary fiber or they may become constipated. Patients who have had a bowel obstruction or have undergone bowel surgery (for example, a colostomy) should not eat a high-fiber diet.



• Drink a warm or hot drink about one half-hour before the patient's usual time for a bowel movement.



• Provide privacy and quiet time when the patient needs to have a bowel movement.



• Help the patient to the toilet or provide a bedside commode instead of a bedpan.



• Take only medications prescribed by the doctor.



• Do not use suppositories or enemas unless ordered by the doctor. In some cancer patients, these treatments may lead to bleeding, infection, or other harmful side effects.

Impaction

Description and Causes

Five major factors can cause impaction:

1. Opioid pain medications.
2. Inactivity over a long period.
3. Changes in diet.
4. Mental illness.
5. Long-term use of laxatives.

   Regular use of laxatives for constipation contributes most to the development of constipation and impaction. Repeated use of laxatives in higher and higher doses makes the colon less able to signal the need to have a bowel movement. (Refer to the Constipation section for causes of constipation that can result in impaction.)

Patients with impaction may have symptoms similar to patients with constipation, or they may have back pain (the impaction presses on sacral nerves) or bladder problems (the impaction presses on the ureters, bladder, or urethra). The patient's abdomen may become enlarged causing difficulty breathing, rapid heartbeat, dizziness, and low blood pressure. Other symptoms can include explosive diarrhea (as stool moves around the impaction), leaking stool when coughing, nausea, vomiting, abdominal pain, and dehydration. Patients who have an impaction may become very confused and disoriented with rapid heartbeat, sweating, fever, and high or low blood pressure.

The doctor will ask questions similar to those in the Assessment of Constipation section and do a physical examination to find out if the patient has an impaction. The examination may also include x-rays of the abdomen and/or chest, blood tests, and an electrocardiogram (a test that shows the activity of the heart).

Impactions are usually treated by moistening and softening the stool with an enema. Enemas must be given very carefully as prescribed by the doctor since too many enemas can damage the bowel. Some patients may need to have stool manually removed from the rectum after it is softened. Glycerin suppositories may also be prescribed. Laxatives that stimulate the bowel and cause cramping must be avoided since they can damage the bowel even more.

Bowel Obstruction

Description and Causes

A bowel obstruction may be caused by a narrowing of the intestine from inflammation or damage to the bowel, tumors, scar tissue, hernias, twisting of the bowel, or pressure on the bowel from outside the intestinal tract. It can also be caused by factors that interfere with the function of muscles, nerves, and blood flow to the bowel. Most bowel obstructions occur in the small intestine and are usually caused by scar tissue or hernias. The rest occur in the colon (large intestine) and are usually caused by tumors, twisting of the bowel, or diverticulitis. Symptoms will vary depending on whether the small or large intestine is involved.

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 abdominal surgery or radiation are at a higher risk of developing a bowel obstruction. Bowel obstructions are most common during the advanced stages of cancer.

The doctor will do a physical examination to find out whether the patient has abdominal pain, vomiting, or any movement of gas or stool in the bowel. Blood and urine tests may be done to detect any fluid and blood chemistry imbalances or infection. Abdominal x-rays and a barium enema may also be done to find the location of the bowel obstruction.

Patients who have abdominal symptoms that continue to become worse must be monitored frequently to prevent or detect early signs and symptoms of shock and constricting obstruction of the bowel. Medical treatment is necessary to prevent fluid and blood chemistry imbalances and shock.

A nasogastric tube may be inserted through the nose and esophagus into the stomach, or a colorectal tube may be inserted through the rectum into the colon to relieve pressure from a partial bowel obstruction. The nasogastric tube or colorectal tube may decrease swelling, remove fluid and gas build-up, or decrease the need for multiple surgical procedures; however, surgery may be necessary if the obstruction completely obstructs the bowel.

Patients who have advanced cancer may have chronic, worsening bowel obstruction that cannot be removed with surgery. Sometimes, the doctor may be able to insert an expandable metal tube called a stent into the bowel to open the area that is blocked.

When neither surgery nor a stent placement is possible, the doctor may insert a gastrostomy tube through the wall of the abdomen directly into the stomach by a very simple procedure. The gastrostomy tube can relieve fluid and air build-up in the stomach and allow medications and liquids to be given directly into the stomach by pouring them down the tube. A drainage bag with a valve may also be attached to the gastrostomy tube. When the valve is open, the patient may be able to eat or drink by mouth without any discomfort because the food drains directly into the bag. This gives the patient the experience of tasting the food and keeping the mouth moist. Solid food should be avoided because it may block the tubing to the drainage bag.

If the patient's comfort is not improved with a stent or gastrostomy tube, and the patient cannot take anything by mouth, the doctor may prescribe injections or infusions of medications for pain and/or nausea and vomiting.

Diarrhea

Causes

In cancer patients, the most common cause of diarrhea is cancer treatment (chemotherapy, radiation therapy, bone marrow transplantation, or surgery). Other causes of diarrhea include antibiotic therapy, stress and anxiety related to being diagnosed with cancer and undergoing cancer treatment; and infection. Infection may be caused by viruses, bacteria, fungi, or other harmful microorganisms. Antibiotic therapy can cause inflammation of the lining of the bowel, resulting in diarrhea that often does not respond to treatment. Other causes of diarrhea in cancer patients include:

• The cancer itself.
• Physical reactions to diet.
• Medical problems and diseases other than cancer.
• The laxative regimen.
• Bowel impaction with leakage of stool around the blockage.

Undergoing surgery to the stomach and/or intestines can affect normal bowel function and cause diarrhea. Some chemotherapy drugs cause diarrhea by affecting how nutrients are broken down and absorbed in the small bowel. Radiation therapy to the abdomen and pelvis can cause inflammation of the bowel. Patients may have problems digesting food, and experience gas, bloating, cramping, and diarrhea. These symptoms may last up to 8 to 12 weeks after therapy or may not develop for months or years. Treatment may include diet changes, medications, or surgery. Patients who are undergoing radiation therapy while receiving chemotherapy often experience severe diarrhea. Hospitalization may not be required, since an outpatient clinic or special home care nursing may give the care and support needed. Each patient's symptoms should be evaluated to determine if intravenous fluids or special medication should be prescribed.

Patients who undergo donor bone marrow transplantation may develop graft-versus-host disease (GVHD). Stomach and intestinal symptoms of GVHD include nausea and vomiting, severe abdominal pain and cramping, and watery, green diarrhea. Symptoms may occur 1 week to 3 months after transplantation. Some patients may require long-term treatment and diet management.

Because diarrhea can be life-threatening, it is important to identify the cause so treatment can begin as soon as possible. The doctor may ask the following questions:

• How often have you had bowel movements in the past 24 hours?
• When was your last bowel movement? What was it like (how much, how hard or soft, what color)? Was there any blood?
• Have you been dizzy, extremely drowsy, or had any cramping, abdominal pain, nausea, vomiting, fever, or rectal bleeding?
• What have you eaten? What and how much have you had to drink in the past 24 hours?
• Have you lost weight recently? How much?
• How often have you urinated in the past 24 hours?
• What medicine are you taking? How much and how often?
• Have you traveled recently?

The doctor will also do a physical examination that should include checking blood pressure, pulse, and respirations; evaluation of the skin and tissue lining the inside of the mouth to check for blood circulation and amount of fluid in the tissue; examination of the abdomen for pain, tenderness, and bowel sounds; and a rectal exam to check for stool impaction and collect stool to test for blood.

Stool may be tested in the laboratory to check for bacterial, fungal, or viral infections. Blood and urine tests may be done to detect fluid and blood chemistry imbalances or infection.

In some cases, abdominal x-rays may also be done to identify bowel obstruction or other abnormalities. In rare cases, a thorough examination of the rectum and colon may be done with a lighted tube inserted through the anus and into the colon.

Diarrhea is treated by identifying and treating the problems causing diarrhea. For example, diarrhea may be caused by stool impaction and medications to prevent constipation. The doctor may make changes in medications, diet, and fluids. Diet changes that may help decrease diarrhea include eating small frequent meals and avoiding some of the following foods:

• Milk and dairy products.
• Spicy foods.
• Alcohol.
• Caffeine-containing foods and drinks.
• Some fruit juices.
• Gas-forming foods and drinks.
• High- fiber foods.
• High-fat foods.

For mild diarrhea, a diet of bananas, rice, apples, and toast (the BRAT diet) may decrease the frequency of stools. Patients should be encouraged to drink up to 3 quarts of clear fluids per day including water, sports drinks, broth, weak decaffeinated tea, caffeine-free soft drinks, clear juices, and gelatin. For severe diarrhea, the patient may need intravenous fluids or other forms of intravenous nutrition. (Refer to the PDQ summary on Nutrition in Cancer Care ¹.)

To manage diarrhea caused by graft-versus-host disease (GVHD), the doctor may recommend a special 5-phase diet. During phase 1, the patient receives intravenous fluids and nothing by mouth to rest the bowel until the diarrhea slows down. In phase 2, the patient may begin drinking fluids. If the patient is able to drink fluids and the diarrhea improves, he or she may begin phase 3, eating solid foods that are low-fiber, low-fat, low-acid, and do not irritate the stomach. In phase 4, the patient is gradually allowed to eat regular foods. If the patient is able to eat regular foods without any episodes of diarrhea, he or she may begin phase 5, eating their regular diet. Many patients may continue to have problems digesting milk and dairy products.

Depending on the cause of the diarrhea, the doctor may change the laxative therapy regimen or may prescribe medications that slow down bowel activity, decrease bowel fluid secretions, and allow nutrients to be absorbed by the bowel.

Radiation Enteritis

Causes and Symptoms

Radiation therapy stops the growth of rapidly dividing cells, such as cancer cells. Since normal cells in the lining of the bowel also divide rapidly, radiation treatment can stop those cells from growing, making it difficult for bowel tissue to repair itself. As bowel cells die and are not replaced, gastrointestinal problems develop over the next few days and weeks.

Acute Enteritis

Patients with acute enteritis may have the following symptoms:

• Nausea.
• Vomiting.
• Abdominal cramps.
• Frequent urges to have a bowel movement.
• Rectal pain, bleeding, or mucus -like discharge.
• Watery diarrhea.

With diarrhea, the gastrointestinal tract does not function normally, and nutrients such as fat, lactose, bile salts, and vitamin B ₁₂ are not well absorbed.

Symptoms of acute enteritis usually get better 2 to 3 weeks after treatment ends.

Chronic Enteritis

Patients with chronic enteritis may have the following symptoms:

• Wave-like abdominal pain.
• Bloody diarrhea.
• Frequent urges to have a bowel movement.
• Greasy and fatty stools.
• Weight loss.
• Nausea.
• Vomiting.

Less common symptoms of chronic enteritis are bowel obstruction, holes in the bowel, and heavy rectal bleeding.

Symptoms usually appear 6 to 18 months after radiation therapy ends. Before determining that chronic radiation enteritis is causing these symptoms, recurrent tumors need to be ruled out. The radiation history of the patient is important in making the correct diagnosis.

Patients will be given a physical exam and be asked questions about the following:

• Usual pattern of bowel movements.
• Pattern of diarrhea, including when it started; how long it has lasted; frequency, amount, and type of stools; and other symptoms (such as gas, cramping, bloating, urgency, bleeding, and rectal soreness).
• Nutritional health of the patient, including height and weight, usual eating habits, any change in eating habits, amount of fiber in the diet, and signs of dehydration (such as poor skin tone, increased weakness, or feeling very tired).
• Current level of stress, ability to cope, and changes in lifestyle caused by the enteritis.

Treatment of acute enteritis includes treating the diarrhea, loss of fluids, poor absorption, and stomach or rectal pain. These symptoms usually get better with medications, changes in diet, and rest. If symptoms become worse even with this treatment, then cancer treatment may have to be stopped, at least temporarily.

Medications that may be prescribed include antidiarrheals to stop diarrhea, opioids to relieve pain, and steroid foams to relieve rectal inflammation and irritation. If patients with pancreatic cancer have diarrhea during radiation therapy, they may need pancreatic enzyme replacement, because not having enough of these enzymes can cause diarrhea.

Nutrition

Nutrition also plays a role in acute enteritis. Intestines damaged by radiation therapy may not make enough or any of certain enzymes needed for digestion, especially lactase. Lactase is needed for the digestion of milk and milk products. A lactose-free, low-fat, and low-fiber diet may help to control symptoms of acute enteritis.

Foods to avoid:

• Milk and milk products, except buttermilk and yogurt. Processed cheese may not cause problems because the lactose is removed during processing. Lactose-free milkshake supplements, such as Ensure, may also be used.
• Whole-bran bread and cereal.
• Nuts, seeds, and coconut.
• Fried, greasy, or fatty foods.
• Fresh and dried fruit and some fruit juices (such as prune juice).
• Raw vegetables.
• Rich pastries.
• Popcorn, potato chips, and pretzels.
• Strong spices and herbs.
• Chocolate, coffee, tea, and soft drinks with caffeine.
• Alcohol and tobacco.

Foods to choose:

• Fish, poultry, and meat that are cooked, broiled, or roasted.
• Bananas, applesauce, peeled apples, and apple and grape juices.
• White bread and toast.
• Macaroni and noodles.
• Baked, boiled, or mashed potatoes.
• Cooked vegetables that are mild, such as asparagus tips, green and waxed beans, carrots, spinach, and squash.
• Mild processed cheese, eggs, smooth peanut butter, buttermilk, and yogurt.

Helpful hints:

• Eat food at room temperature.
• Drink 3 liters (about 12 eight- ounce glasses) of fluid a day.
• Allow carbonated beverages to lose their fizz before drinking them.
• Add nutmeg to food to help decrease movement of the gastrointestinal tract.
• Start a low-fiber diet on the first day of radiation therapy.

Treatment of the symptoms of chronic radiation enteritis is the same as treatment of acute radiation enteritis. Surgery is used to treat severe damage. Fewer than 2% of affected patients will need surgery to control their symptoms.

Two types of surgery may be used:

• Intestinal bypass, a procedure in which the doctor creates a new pathway for the flow of bowel contents.
• Complete removal of the diseased intestines.

The patient's general health and the amount of damaged tissue are considered before surgery is attempted, however, because wound healing is often slow and long-term tubefeeding may be needed. Even after surgery, many patients still have symptoms.

To lower the risk that chronic radiation enteritis will occur, different treatment methods are used to reduce the area that is exposed to radiation. Patients may be positioned to protect as much of the small bowel as possible from the radiation treatment, or may be asked to have a full bladder during treatment to help push the small bowel out of the way. The amount of radiation may be adjusted to deliver lower amounts more evenly or higher amounts to specific areas. If a patient has surgery, clips may be placed at the tumor site to help show the area to be irradiated.

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Changes to This Summary (07/19/2006)

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.

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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 ³. 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.

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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.

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Glossary Terms

The area of the body that contains the pancreas, stomach, intestines, liver, gallbladder, and other organs.

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.

Not normal. An abnormal lesion or growth may be cancerous, premalignant (likely to become cancer), or benign.

Symptoms or signs that begin and worsen quickly; not chronic.

A drug used to treat infections caused by bacteria and other microorganisms.

The opening of the rectum to the outside of the body.

Feelings of fear, dread, and uneasiness that may occur as a reaction to stress. A person with anxiety may sweat, feel restless and tense, and have a rapid heart beat. Extreme anxiety that happens often over time may be a sign of an anxiety disorder.

A large group of single-cell microorganisms. Some cause infections and disease in animals and humans. The singular of bacteria is bacterium.

A procedure in which a liquid with barium in it is put into the rectum and colon by way of the anus. Barium is a silver-white metallic compound that helps to show the image of the lower gastrointestinal tract on an x-ray.

A fluid made by the liver and stored in the gallbladder. Bile is excreted into the small intestine, where it helps digest fat.

The organ that stores urine.

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.

A procedure to replace bone marrow that has been destroyed by treatment with high doses of anticancer drugs or radiation. Transplantation may be autologous (an individual's own marrow saved before treatment), allogeneic (marrow donated by someone else), or syngeneic (marrow donated by an identical twin).

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 the intestine.

The way the intestines work in terms of how often there are bowel movements, the ability to control when to have a bowel movement, and whether the stools are hard and dry as in constipation or watery as in diarrhea.

The growth of abnormal cells in the tissues of the brain. Brain tumors can be benign (non-cancerous) or malignant (cancerous).

Cancer that forms in tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). It occurs in both men and women, although male breast cancer is rare.

A surgical procedure in which the doctor creates a new pathway for the flow of body fluids.

A mineral found in teeth, bones, and other body tissues.

A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is 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.

Having to do with the heart.

The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

Treatment with drugs that kill cancer cells.

A disease or condition that persists or progresses over a long period of time.

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 a clinical study.

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.

Having to do with the colon or the rectum.

An opening into the colon from the outside of the body. A colostomy provides a new path for waste material to leave the body after part of the colon has been removed.

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.

A condition caused by the loss of too much water from the body. Severe diarrhea or vomiting can cause dehydration.

A mental condition marked by ongoing feelings of sadness, despair, loss of energy, and difficulty dealing with normal daily life. Other symptoms of depression include feelings of worthlessness and hopelessness, loss of pleasure in activities, changes in eating or sleeping habits, and thoughts of death or suicide. Depression can affect anyone, and can be successfully treated. Depression affects 15-25% of cancer patients.

A disease in which the body does not properly control the amount of sugar in the blood. As a result, the level of sugar in the blood is too high. This disease occurs when the body does not produce enough insulin or does not use it properly.

The process of identifying a disease, such as cancer, from its signs and symptoms.

The thin muscle below the lungs and heart that separates the chest from the abdomen.

Frequent and watery bowel movements.

The things a person eats and drinks.

DRE. An examination in which a doctor inserts a lubricated, gloved finger into the rectum to feel for abnormalities. Also called DRE.

In medicine, a disturbance of normal functioning of the mind or body. Disorders may be caused by genetic factors, disease, or trauma.

A drug that increases the production of urine.

The amount of medicine taken, or radiation given, at one time.

Any substance, other than food, that is used to prevent, diagnose, treat or relieve symptoms of a disease or abnormal condition. Also refers to a substance that alters mood or body function, or that can be habit-forming or addictive, especially a narcotic.

A state of not functioning normally.

The injection of a liquid through the anus into the large bowel.

A protein that speeds up chemical reactions in the body.

The muscular tube through which food passes from the throat to the stomach.

A condition marked by extreme tiredness and inability to function due lack of energy. Fatigue may be acute or chronic.

In food, fiber is the part of fruits, vegetables, legumes, and whole grains that cannot be digested. The fiber in food may help prevent cancer. In the body, fiber refers to tissue made of long threadlike cells, such as muscle fiber or nerve fiber.

Liquid.

A plant-like organism that does not make chlorophyll. Mushrooms, yeasts, and molds are examples. The plural is fungi.

GI. Refers to the stomach and intestines. Also called GI.

Drugs that cause loss of feeling or awareness and put the person to sleep.

A disease caused when cells from a donated stem cell graft attack the normal tissue of the transplant patient. Symptoms include jaundice, skin rash or blisters, a dry mouth, or dry eyes. Also called GVHD.

A blood pressure of 140/90 or higher. Hypertension usually has no symptoms. It can harm the arteries and cause an increase in the risk of stroke, heart attack, kidney failure, and blindness. Also called high blood pressure.

A type of radiation therapy in which radioactive material sealed in needles, seeds, wires, or catheters is placed directly into or near a tumor. Also called brachytherapy, radiation brachytherapy, and internal radiation therapy.

Invasion and multiplication of germs in the body. Infections can occur in any part of the body and can spread throughout the body. The germs may be bacteria, viruses, yeast, or fungi. They can cause a fever and other problems, depending on where the infection occurs. When the body’s natural defense system is strong, it can often fight the germs and prevent infection. Some cancer treatments can weaken the natural defense system.

Redness, swelling, pain, and/or a feeling of heat in an area of the body. This is a protective reaction to injury, disease, or irritation of the tissues.

Having to do with inflammation (redness, swelling, pain, and a feeling of heat that helps protect tissues affected by injury or disease).

A method of putting fluids, including drugs, into the bloodstream. Also called intravenous infusion.

Use of a syringe and needle to push fluids or drugs into the body; often called a "shot."

Having to do with the intestines.

The long, tube-shaped organ in the abdomen that completes the process of digestion. The intestine has two parts, the small intestine and the large intestine. Also called the bowel.

Into or within a vein. Intravenous usually refers to a way of giving a drug or other substance through a needle or tube inserted into a vein. Also called I.V.

An important mineral the body needs to make hemoglobin, a substance in the blood that carries oxygen from the lungs to tissues throughout the body. Iron is also an important part of many other proteins and enzymes needed by the body for normal growth and development. It is found in red meat, fish, poultry, lentils, beans, and foods with iron added, such as cereal.

Treated with radiation.

One of a pair of organs in the abdomen. Kidneys remove waste from the blood (as urine), produce erythropoietin (a substance that stimulates red blood cell production), and play a role in blood pressure regulation.

A type of sugar found in milk and milk products.

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.

A substance that promotes bowel movements.

Cancer that forms in tissues of the lung, usually in the cells lining air passages. The two main types are small cell lung cancer and non-small cell lung cancer. These types are diagnosed based on how the cells look under a microscope.

A form of cancer that begins in melanocytes (cells that make the pigment melanin). It may begin in a mole (skin melanoma), but can also begin in other pigmented tissues, such as in the eye or in the intestines.

An organism that can be seen only through a microscope. Microorganisms include bacteria, protozoa, algae, and fungi. Although viruses are not considered living organisms, they are sometimes classified as microorganisms.

A thick, slippery fluid made by the membranes that line certain organs of the body, including the nose, mouth, throat, and vagina.

The National Cancer Institute, part of the National Institutes of Health of the United States Department of Health and Human Services, is the Federal Government's principal agency for cancer research. The National Cancer Institute conducts, coordinates, and funds cancer research, training, health information dissemination, and other programs with respect to the cause, diagnosis, prevention, and treatment of cancer. Access the National Cancer Institute Web site at http://www.cancer.gov. Also called NCI.

A feeling of sickness or discomfort in the stomach that may come with an urge to vomit. Nausea is a side effect of some types of cancer therapy.

A bundle of fibers that receives and sends messages between the body and the brain. The messages are sent by chemical and electrical changes in the cells that make up the nerves.

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.

The taking in and use of food and other nourishing material by the body. Nutrition is a 3-part process. First, food or drink is consumed. Second, the body breaks down the food or drink into nutrients. Third, the nutrients travel through the bloodstream to different parts of the body where they are used as "fuel" and for many other purposes. To give the body proper nutrition, a person has to eat and drink enough of the foods that contain key nutrients.

Blockage of a passageway.

A drug used to treat moderate to severe pain. Opioids are similar to opiates such as morphine and codeine, but they do not contain and are not made from opium.

A part of the body that performs a specific function. For example, the heart is an organ.

A measure of weight (one-sixteenth pound) and volume (one-eighth cup).

A patient who visits a health care facility for diagnosis or treatment without spending the night. Sometimes called a day patient.

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.

A disease in which malignant (cancer) cells are found in the tissues of the pancreas. Also called exocrine cancer.

A protein secreted by the pancreas that aids in the digestion of food.

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.

The lower part of the abdomen, located between the hip bones.

An exam of the body to check for general signs of disease.

A metallic element that is important in body functions such as regulation of blood pressure and of water content in cells, transmission of nerve impulses, digestion, muscle contraction, and heartbeat.

A doctor's order for medicine or another intervention.

In medicine, action taken to decrease the chance of getting a disease or condition. For example, cancer prevention includes avoiding risk factors (such as smoking, obesity, lack of exercise, and radiation exposure) and increasing protective factors (such as getting regular physical activity, staying at a healthy weight, and having a healthy diet).

Inflammation of the small intestine caused by radiation therapy to the abdomen, pelvis, or rectum. Symptoms include nausea, vomiting, abdominal pain and cramping, frequent bowel movements, watery or bloody diarrhea, fatty stools, and weight loss. Some of these symptoms may continue for a long time.

The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called radiotherapy and irradiation.

By or having to do with the rectum. The rectum is the last several inches of the large intestine closest to the anus.

The last several inches of the large intestine closest to the anus.

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.

A treatment plan that specifies the dosage, the schedule, and the duration of treatment.

The organs that are involved in breathing. These include the nose, throat, larynx, trachea, bronchi, and lungs. Also called respiratory tract.

The large, triangle-shaped bone in the lower spine that forms part of the pelvis. It is made of 5 fused bones of the spine.

Checking for disease when there are no symptoms. Since screening may find diseases at an early stage, there may be a better chance of curing the disease. Examples of cancer screening tests are the mammogram (breast), colonoscopy (colon), Pap smear (cervix), and PSA blood level and digital rectal exam (prostate). Screening can also include checking for a person’s risk of developing an inherited disease by doing a genetic test.

A problem that occurs when treatment affects healthy tissues or organs. Some common side effects of cancer treatment are fatigue, pain, nausea, vomiting, decreased blood cell counts, hair loss, and mouth sores.

The part of the digestive tract that is located between the stomach and the large intestine.

A mineral needed by the body to keep body fluids in balance. Sodium is found in table salt and in many processed foods. Too much sodium can cause the body to retain water.

A column of nerve tissue that runs from the base of the skull down the back. It is surrounded by three protective membranes, and is enclosed within the vertebrae (back bones). The spinal cord and the brain make up the central nervous system, and spinal cord nerves carry most messages between the brain and the rest of the body.

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.

A device placed in a body structure (such as a blood vessel or the gastrointestinal tract) to keep the structure open.

A type of drug used to relieve swelling and inflammation. Some steroid drugs may also have antitumor effects.

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.

The material in a bowel movement. Stool is made up of food that was not digested, bacteria, mucus, and cells from the intestines. Also called feces.

In medicine, a loss of blood flow to part of the brain, which damages brain tissue. Strokes are caused by blood clots and broken blood vessels in the brain. Symptoms include dizziness, numbness, weakness on one side of the body, and problems with talking, writing, or understanding language. The risk of stroke is increased by high blood pressure, older age, smoking, diabetes, high cholesterol, heart disease, atherosclerosis (a build-up of fatty material and plaque inside the coronary arteries), and a family history of stroke.

A substance or product that is added to a person’s diet to make sure they get all the nutrients they need. It may include vitamins, minerals, protein, or fat, and may be given by mouth, by tube feeding, or into a vein.

Adding nutrients to the diet.

Care given to improve the quality of life of patients who have a serious or life-threatening disease. The goal of supportive care is to prevent or treat as early as possible the symptoms of a disease, side effects caused by treatment of a disease, and psychological, social, and spiritual problems related to a disease or its treatment. Also called palliative care, comfort care, and symptom management.

A procedure to remove or repair a part of the body or to find out whether disease is present. An operation.

An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.

Treatment.

A gland located beneath the voice box (larynx) that produces thyroid hormone. The thyroid helps regulate growth and metabolism.

A group or layer of cells that work together to perform a specific function.

A plant with leaves that have high levels of the addictive chemical nicotine. The leaves may be smoked (in cigarettes, cigars, and pipes), applied to the gums (as dipping and chewing tobacco), or inhaled (as snuff). Tobacco leaves also contain many cancer-causing chemicals, and tobacco use and exposure to secondhand tobacco smoke have been linked to many types of cancer and other diseases. The scientific name is Nicotiana tabacum.

A type of enteral nutrition (nutrition that is delivered into the digestive system in a liquid form). For tubefeeding, a small tube may be placed through the nose into the stomach or the small intestine. Sometimes it is surgically placed into the stomach or the intestinal tract through an opening made on the outside of the abdomen, depending on how long it will be used. People who are unable to meet their needs with food and beverages alone, and who do not have vomiting or uncontrollable diarrhea may be given tubefeedings. Tubefeeding can be used to add to what a person is able to eat or can be the only source of nutrition.

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 cancerous), or malignant (cancerous). Also called neoplasm.

The tube that carries urine from the kidney to the bladder.

The tube through which urine leaves the body. It empties urine from the bladder.

Fluid containing water and waste products. Urine is made by the kidneys, stored in the bladder, and leaves the body through the urethra.

In medicine, a very simple microorganism that infects cells and may cause disease. Because viruses can multiply only inside infected cells, they are not considered to be alive.

A key nutrient that the body needs in small amounts to grow and stay strong. Examples are vitamins A, C, and E.

A vitamin that is needed to make red blood cells and DNA (the genetic material in cells) and to keep nerve cells healthy. It is found in eggs, meat, poultry, shellfish, milk, and milk products. Vitamin B12, along with folate, may be given to help reduce side effects in cancer patients being treated with drugs called antimetabolites. Also called cobalamin.

To eject some or all of the contents of the stomach through the mouth.

A break in the skin or other body tissues caused by injury or surgical incision (cut).

A type of high-energy radiation. In low doses, x-rays are used to diagnose diseases by making pictures of the inside of the body. In high doses, x-rays are used to treat cancer.