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Glossary

A Few Terms to Know

Adherence: A patient's willingness to follow treatment procedures precisely as advised by the doctor, such as taking medicine at a certain time each day.

Adjuvant treatment: A treatment used in addition to the main treatment for an illness. More specifically, it is therapy given after surgery.

Anemia: Low levels of red blood cells. This can cause symptoms of fatigue, dizziness, fainting, and weakness.

Cancer: A condition that develops when cells in a part of the body begin to grow out of control because of damage to DNA.

Chemotherapy: Drug therapy intended to kill tumor cells or prevent them from growing.

Chromosome: Found in the nucleus of the cell, these structures contain the cell's genes.

Computed tomography (CT) scan: The most common scan your doctor will use to measure the size and number of your tumors.

c-kit: The name of the gene that contains instructions for manufacturing the "KIT" protein. When referring to the gene itself, doctors use the term "c-kit." When referring to the protein made by the gene, they say, "KIT".

Deoxyribonucleic acid (DNA): The substance in every cell that directs the cell's activity, including telling the cell when to divide.

Endoscopic ultrasound (EUS): EUS may be used to determine the cause of symptoms such as abdominal pain, to evaluate a growth (tumor), and to diagnose diseases of the digestive tract and lungs.

Gastroenterologist: A doctor who specializes in treating conditions of the stomach and intestines.

Gastrointestinal tract: Where food is processed for energy and solid waste is removed. It includes the esophagus, stomach, small intestine, colon, and rectum. Also called GI tract.

Gene: A gene is the basic unit of heredity passed from parent to child. Genes are made of DNA and carry instructions for making proteins.

GIST: A rare type of tumor in the GI tract. The majority of these tumors start in the stomach or small intestine. GIST stands for Gastrointestinal Stromal Tumor.

Imaging: Scans that enable doctors to take pictures of KIT+ GIST tumors and evaluate a patient's response to treatment. Three common types are called CT, MRI, and PET scans.

Kinase inhibitor: A drug that interferes with cell communication and growth, and which may prevent the growth of tumors.

KIT: A protein that tells cells to grow and divide as needed.

KIT-positive (KIT+) GIST: A type of GIST in which the KIT protein is constantly active, or "on." This defect causes a tumor to develop where cells grow and divide abnormally.

Localized: A localized tumor (also called a primary tumor) is one that has not spread from its original location.

Magnetic resonance imaging (MRI) scan: An MRI scan uses radio waves and giant magnets to create detailed scans of the body. These help determine if tumors have spread or returned.

Metastatic: A tumor that has spread to a part of the body beyond its original location.

Oncologist: A doctor specializing in the diagnosis and treatment of cancer. Their role is to explain the diagnosis as well as discuss various treatment options and recommend the best course of treatment.

Positron emission tomography (PET) scan: This scan is helpful for identifying whether or not tumor cells are alive or dead, regardless of whether the tumor has shrunk.

Prognosis: The likely outcome of treatment for an illness.

Radiation: A form of treatment that destroys cancer cells using a focused beam of atomic particles or electromagnetic waves (such as X-rays).

Radiologist: A physician who uses radiation to diagnose and treat diseases.

Response: A measure of how well a treatment is working.

Recurrence: The return of cancer after treatment.

Stroma: The type of cell where GIST begins. Located along the GI tract, these cells are part of the system that signals the body to help move food through the digestive system.

Surgeon: A physician who specializes in performing operations — in the case of GIST, to remove a tumor.

Unresectable: A tumor that cannot be completely removed by surgery.

X-ray: A 2-dimensional picture of parts of the body taken using small amounts of radiation.

*Eligible patients are those being treated with GLEEVEC for KIT+ GIST and who reside in the U.S. and Puerto Rico. Residents of Massachusetts and patients participating in a federal or state government-related healthcare program that pays in whole or in part for prescription drugs are not eligible.

 

 

Side Effects

Almost all people taking GLEEVEC experience side effects.

Be sure to talk to your doctor and/or healthcare professional about any GLEEVEC side effects you are experiencing.

Serious side effects include:

  • Severe fluid retention, which can cause swelling around the eyes or swelling of the lower legs, lungs, and heart; fatal in rare cases (reported in 9%–13.1% of patients)
  • Increased pressure in the heart or brain; fatal in rare cases
  • Low levels of certain blood cells
  • Heart failure
  • Liver problems
  • Hemorrhage (abnormal bleeding) [reported in 12.9% of patients in Phase 3 studies and 5% of patients in the Phase 2 study]
  • Skin blistering
  • Low levels of thyroid hormone

Some common side effects are:

  • Fluid retention
  • Muscle cramps or pain and bone pain
  • Abdominal pain
  • Vomiting
  • Diarrhea
  • Decreased hemoglobin (an oxygen-carrying protein in red blood cells)
  • Nausea
  • Fatigue
  • Rash
  • Anorexia (loss of appetite)

Supportive care may help reduce the severity of some side effects, whereas others require discontinuation or dosage adjustment. Don't stop taking your medication or change your dose without talking to your doctor.

GLEEVEC can cause fetal harm when administered to a pregnant woman. Women should be aware of the potential harm to the fetus. Be sure to inform your doctor if you are or think you may be pregnant. You should not breast-feed while taking GLEEVEC.

Side effects

What it feels like

How your doctor may manage it

Swelling and fluid retention

Swollen legs or feet and swelling around the eyes. Fluid retention can appear as quick weight gain or swelling in your lower legs or other parts of your body. Fluid retention can be serious or even life-threatening
  • Regular check-ups to monitor your weight
  • Prescribe a topical steroid cream to reduce the swelling around your eyes
  • Tell you to limit your salt intake
  • Prescribe a diuretic (a medicine to help your body get rid of extra fluids)

Rash

Scaly skin; red itchy bumps on skin
  • Recommend an over-the-counter (OTC) antihistamine
  • Prescribe a corticosteroid or stronger antihistamine

Nausea and vomiting

Feeling queasy or like you have to throw up

You may also feel like you have indigestion

  • Recommend taking GLEEVEC with a meal and a large glass of water (If you have been instructed not to take GLEEVEC with meals, contact your doctor before changing your dose to mealtimes)
  • Recommend OTC medications
  • If you are taking your GLEEVEC once a day, talk to your doctor about possibly dividing the dose in half and taking it twice a day

Muscle cramps

Pain or spasms in the legs, feet, or calves
  • Recommend an OTC pain reliever, like ibuprofen
  • Recommend a prescription pain reliever
  • Recommend calcium and magnesium supplements

Muscle and bone pain

Whole-body ache; twitching or burning muscles
  • Recommend an OTC pain reliever, like ibuprofen
  • Recommend a prescription pain reliever

Diarrhea

More bowel movements; loose stools
  • Recommend an OTC medication
Important information

GLEEVEC® is available only by prescription.

GLEEVEC® Indications
  • GLEEVEC® (imatinib mesylate) tablets are indicated for the treatment of patients with Kit (CD117)–positive gastrointestinal stromal tumors (GIST) that are cancerous, cannot be surgically removed, and/or have spread to other parts of the body
  • GLEEVEC is also approved for use after surgery in patients that have had their Kit (CD117)–positive GISTs completely removed. Approval is based on survival without a return of cancer (recurrence-free survival) with a median follow-up of 14 months. Clinical benefit has not been demonstrated by a long-term effect on recurrence-free survival or survival

SAFETY: Important product information (Click here for full Prescribing Information)

Who should NOT take GLEEVEC
  • Women who are or could be pregnant. Fetal harm can occur when administered to pregnant women; therefore, women should not become pregnant, as well as be advised of the potential risk to the unborn child if GLEEVEC is used during pregnancy
  • Women who are breast-feeding because of the potential for serious adverse reactions in nursing infants
  • Sexually active females should use adequate birth control while taking GLEEVEC

Be sure to talk to your doctor and/or healthcare professional about these issues before taking GLEEVEC.

Warnings and precautions
  • GLEEVEC is often associated with edema (swelling) and serious fluid retention. It is important that patients be weighed and monitored regularly for signs and symptoms of serious fluid retention, or unexpected weight gain. Patients experiencing unexpected rapid weight gain should speak to their doctor about appropriate supportive care treatment. Studies have shown that edema (swelling) tended to occur more often among patients who are 65 and older or those taking higher doses of GLEEVEC. If you experience severe fluid retention, your doctor may treat you with diuretics and may stop your GLEEVEC treatment until the fluid retention has been managed
  • Cytopenias (reduction or lack of certain cell elements in blood circulation), such as anemia, have occurred. Your doctor will perform complete blood counts weekly for the first month, biweekly for the second month, and periodically thereafter. In most cases, your doctor will reduce or interrupt your GLEEVEC therapy; in rare cases, your doctor may discontinue treatment. If the cytopenia is severe, your doctor may reduce your dose or temporarily stop your treatment with GLEEVEC
  • Severe congestive heart failure and left ventricle dysfunction have been reported, particularly in patients with other health issues and risk factors. Patients with heart disease or risk factors will be monitored and treated for the condition
  • Severe liver problems (hepatotoxicity) may occur. Cases of fatal liver failure and severe liver injury requiring liver transplants have been reported with both short-term and long-term use of GLEEVEC. Your doctor will check your liver function before beginning treatment and continue to monitor liver function as needed. If you experience severe liver problems, your doctor may stop your treatment with GLEEVEC until the liver problem has been managed
  • Bleeding may occur. Severe gastrointestinal (GI) bleeding has been reported in patients with KIT+ GIST. GI tumor sites may be the cause of this bleeding
  • In patients with hypereosinophilic syndrome (a condition with increased eosinophils, which are a type of white blood cell) and heart involvement, cases of heart disease (cardiogenic shock/left ventricular dysfunction) have been associated with the initiation of GLEEVEC therapy. Speak to your doctor regarding appropriate supportive care or discontinuing GLEEVEC
  • Skin reactions, such as fluid-filled blisters, have been reported with the use of GLEEVEC
  • Clinical cases of hypothyroidism (reduction in thyroid hormones) have been reported in patients taking levothyroxine replacement during treatment with GLEEVEC. Your doctor should closely monitor your thyroid hormone levels
  • Long-term use may result in potential liver, kidney, and/or heart toxicities; immune system suppression may also result from long-term use
  • GLEEVEC can cause fetal harm when administered to a pregnant woman. Women should be aware of the potential harm to the fetus. Be sure to inform your doctor if you are or think you may be pregnant. You should not breast-feed while taking GLEEVEC
  • GI perforation (small holes or tears in the walls of the stomach or intestine), in some cases fatal, has been reported
  • Growth retardation has been reported in children taking GLEEVEC. The long-term effects of extended treatment with GLEEVEC on growth in children are unknown. Growth retardation may be monitored in children receiving treatment
  • Cases of tumor lysis syndrome (TLS), which refers to a metabolic and electrolyte disturbance caused by the breakdown of tumor cells, have been reported and can be life-threatening in some cases. The patients at risk of TLS are those that have a higher amount of tumor cells and whose tumors are fast-growing before beginning therapy. Your doctor should monitor you closely and take appropriate precautions
Important safety information

The following serious side effects have been reported in patients taking GLEEVEC:

  • Severe fluid retention, which can cause swelling around the eyes or swelling of the lower legs, lungs, and heart; fatal in rare cases
  • Increased pressure in the heart or brain; fatal in rare cases
  • Low levels of certain blood cells
  • Heart failure
  • Liver problems
  • Hemorrhage (abnormal bleeding)
  • Skin blistering
  • Low levels of thyroid hormone

Your doctor will check you closely for any side effects to stop more serious complications from occurring. Patients with heart disease or risk factors for heart failure should also be monitored carefully.

GLEEVEC is sometimes associated with stomach or intestinal irritation. GLEEVEC should be taken with food and a large glass of water to minimize this problem. There have been rare reports, including deaths, of stomach or intestinal perforation (a small hole or tear).

If you are experiencing any of the above-mentioned side effects, please be sure to speak with your doctor immediately.

Common side effects of GLEEVEC

Almost all patients with KIT+ GIST treated with GLEEVEC experience side effects at some time. In various studies, a range of 5%-17% of patients stopped taking GLEEVEC due to side effects. Some common side effects you may experience include:

  • Fluid retention
  • Muscle cramps or pain and bone pain
  • Abdominal pain
  • Vomiting
  • Diarrhea
  • Decreased hemoglobin
  • Nausea
  • Fatigue
  • Rash
  • Anorexia (loss of appetite)

If you are experiencing any of the above-mentioned side effects, please be sure to speak with your doctor immediately.

The severity of some side effects may be reduced with the help of other medicines and advice from your doctor, while others may require stopping GLEEVEC therapy or changing the dose. However, in some cases, GLEEVEC therapy may need to be discontinued.

Tell your doctor if you experience side effects during therapy with GLEEVEC, including fever, shortness of breath, blood in your stools, jaundice (yellowing of the skin and/or eyes), sudden weight gain, symptoms of heart failure, or if you have a history of heart disease or risk factors for heart disease.

After the approval of GLEEVEC, the following adverse events have been reported in patients treated with GLEEVEC: compression of the heart due to increased fluid, swelling of the brain, GI perforation (holes in the stomach or intestine), and sudden lung failure. These events, including some fatalities, may or may not have been drug related.

Take GLEEVEC exactly as prescribed. Do not change your dose or stop taking GLEEVEC unless you are told to do so by your doctor. If you miss a dose, take your dose as soon as possible, unless it is almost time for your next dose. In this case, your missed dose should not be taken. A double dose should not be taken to make up for any missed dose. You should take GLEEVEC with a meal and a large glass of water.

Do not take any other medications without talking to your doctor or pharmacist first, including over-the-counter medications such as Tylenol® (acetaminophen); herbal products (St. John's wort, Hypericum perforatum); Coumadin® (warfarin sodium); rifampin; erythromycin; metoprolol; ketoconazole; and Dilantin® (phenytoin). Taking these with GLEEVEC may affect how they work, or affect how GLEEVEC works.

You should also tell your doctor if you are taking or plan to take iron supplements. Patients should also avoid grapefruit juice and other foods that may affect how GLEEVEC works.

Tylenol (acetaminophen) is a registered trademark of McNeil Consumer & Specialty Pharmaceuticals, a division of McNeil PPC, Inc. Coumadin (warfarin sodium) is a registered trademark of Bristol Myers Squibb Company. Dilantin (phenytoin) is a registered trademark of Parke-Davis, a division of Pfizer Inc.

Click here for full Prescribing Information