What is chemotherapy?
Drug treatment for cancer is called chemotherapy. The job of chemotherapy is to destroy cancer cells, including those that may have spread beyond the main tumor. Unlike surgery or radiation, most types of chemotherapy, or "chemo," don't target a particular tumor or a particular part of the body, although there are some newer "designer drugs" being developed that seek out and destroy cancer cells specifically. Most forms of chemotherapy attack all rapidly dividing cells, and cancer cells fit that description.
Although cancer cells divide rapidly, other cells do too, including the ones in the lining of your stomach and the ones that grow hair on your head. (That's why chemotherapy patients often lose their hair.) Because the drugs affect all types of cells in your body, you're likely to feel worse after a round of chemotherapy -- at least temporarily. Some drugs have worse side effects than others.
Some people need chemotherapy for only a short time, but others may need treatment off and on for years. The drugs might be able to cure your cancer completely, or they might only be able to give you extra time. It all depends on what kind of cancer you have, how advanced the cancer is and how well it responds to treatment.
In many cases, chemotherapy is only part of the overall treatment plan. It might be used to shrink a tumor before surgery or radiation, or it might be used after surgery or radiation to destroy any remaining cancer cells. It might also be used alongside radiation or biological drugs (immunotherapy) to improve the effectiveness of treatment.
What are the different types of chemotherapy drugs?
Doctors have many options when it comes to chemotherapy, and that list is growing all the time. In April 2009, the Pharmaceutical Research and Manufacturers of America (PhRMA) reported that more than 800 new cancer medicines and vaccines were being tested or awaiting approval by the Food and Drug Administration (FDA). Some drugs are more powerful than others, some have worse side effects, and some work better against particular types of cancer. Your treatment will depend on many factors, including the type of cancer you have, how advanced the disease is, and your overall health. You may take more than one chemotherapy drug at once, and your treatment may change over time. Your doctor will always try to find a balance between treating the disease and maintaining your quality of life.
Here's a brief description of some common chemotherapy drugs:
Doxorubicin (Adriamycin) is one of the most powerful chemotherapy drugs ever invented. It can kill cancer cells at every point in their life cycle, and it's used to treat a wide variety of cancers. Unfortunately, the drug can also damage heart cells, so a patient can't take it indefinitely.
Cyclophosphamide (Cytotoxan) is a drug that can treat many different cancers. Like many other chemotherapy drugs, it scrambles the DNA of cancer cells. Because it damages healthy DNA too, it can also cause long-term injury to the bone marrow, which, in a few rare cases, can lead to a new case of leukemia (cancer of certain white blood cells).
Paclitaxel (Taxol) is an effective drug used for treating some cases of breast cancer and ovarian cancer, but it can damage nerves over time, leaving some people with decreased sensation in their hands and feet. The anticancer compound in this drug was first discovered in the bark of Pacific yew trees.
Fluorouracil (Adrucil) was first approved as a chemotherapy drug in 1962 and is one of the oldest chemotherapy drugs still prescribed today. It's primarily used to treat gastrointestinal cancers (including colon, rectal, stomach) and certain types of breast cancer.
Gemcitabine (Gemzar) is a relatively new chemotherapy drug that is effective at slowing the growth of several types of cancer. Used alone, it's a first-line treatment for pancreatic cancer that has spread or is inoperable. It's also used in combination to treat certain types of breast, ovarian, and lung cancers.
The new "targeted" therapies -- considered by many researchers to be the holy grail of chemotherapy -- do not go after all fast-growing cells but instead attack cells with mutant versions of certain genes or cells that are abnormal in other ways. Examples of these drugs are imatinib (Gleevec), erlotinib (Tarceva), and bortezomib (Velcade).
What will treatment be like?
Chemotherapy is usually given at a hospital or clinic. Chemotherapy drugs are most often given through an intravenous (IV) line. You'll sit or lie down comfortably while the drug slowly drips into your body. This is normally done in a room with other patients, or depending on your condition, you may have a private room.
You might get a catheter, port (a round disc usually placed in the chest), or pump to deliver the drug. The port is inserted via minor surgery and will stay in for as long as you receive chemotherapy. The advantage of a port is that the infusion nurse won't have to start a new IV every time you get chemo. Less often, chemotherapy can be given through a shot, pill, or cream.
Getting a chemo infusion can take anywhere from a couple hours to 24 hours or longer, depending on the type and number of drugs you're getting. Depending on your cancer type, you may receive chemotherapy as an inpatient. You may be told to take anti-nausea drugs beforehand, and those can make you tired and impair your judgment. The whole process may make you feel weak or ill. Make sure you arrange a ride home.
Sometimes chemotherapy can be given at home on a daily basis with a home infusion pump; 5-fluorouracil is one of the drugs administered that way. Sometimes you have to go into the clinic for weekly or monthly infusions with close monitoring.
The drugs are often given in cycles. You may receive your medication every week for several weeks, then take a couple of weeks off to give your body a chance to recover.
What are some of the possible side effects of chemotherapy drugs?
As the above examples show, different types of chemotherapy can have different side effects. Your doctor can tell you what to expect for your specific treatment. Keep in mind that different people's reactions to the same drug can vary. Some people might feel very ill, and others may have only slight side effects. In many cases, side effects can be prevented or greatly reduced with a combination of medications or lifestyle changes.
Here's a brief look at some common side effects:
- Hair loss. Not all types of chemotherapy lead to hair loss, but for the many patients who lose all their hair, this can be the most traumatic part of chemotherapy. Those patients eventually have to come up with a plan for their missing hair: Should they wear a wig, a hat, or a bandanna? Or just keep their bald heads in plain sight? It's a matter of personal preference. The good news is that hair will eventually grow back after you're done with chemo. It may grow back a different color or texture at first, but over time it should start looking closer to the way it was.
- Skin and nail changes. Skin and nails are also fast-growing parts of the body, and chemo drugs can affect them in different ways. Chemo can make you sensitive to the sun, make your veins look darker, or cause itching, redness, or dry skin. Nails might turn yellow or dark, or become brittle or cracked. However, if you notice major skin changes, or if you feel a burning sensation while getting chemo, you should tell your doctor right away. Major skin changes need to be treated right away, or they can cause lifelong problems.
- Nausea. A sick feeling in the stomach can be the most troubling side effect of chemotherapy. You may have heard people tell horror stories about their own nausea and vomiting while on chemotherapy drugs. Yet you could have a completely different experience. Doctors today take nausea very seriously, and there are many medications that can soothe your stomach. Sometimes they are given along with the chemotherapy to prevent the side effects before you get them. Relaxation exercises can also help calm your stomach along with the rest of your body. Nausea may be an ongoing problem for some people, while others have just a few bouts of nausea now and then. .
- Mouth and throat changes. Some people feel a metallic or medicine-like taste in their mouths while on chemo, or develop aversions and cravings -- you might lose your taste for certain foods, like tomatoes or red meat, for example, or develop a sweet tooth. Other effects may include dry mouth, sensitivity, or sores in the mouth or throat. These are all temporary effects, but if they are interfering with your daily life, talk to your doctor.
- Weight changes. Between the nausea and your confused taste buds, it's understandable that you might not have much appetite. But you do need to eat to keep your strength up and so you won't lose too much weight. Small meals or smoothies might go down more easily. In some cases, you might feel extra hungry or gain weight.
- Fatigue. Chemotherapy drugs can deplete your supply of red blood cells, the cells that carry oxygen throughout your body. Anemia, or a shortage of red blood cells, can make you very tired. You may also feel irritable, dizzy, or short of breath. Even if you aren't anemic, the treatment can sap your strength and make it difficult to get through the day. Be sure to tell your doctor about any unusual tiredness. In certain cases, anemia can be treated with drugs that boost red blood cell production, and if symptoms are severe, your doctor may suggest a blood transfusion to temporarily boost your red blood cell count.
- Trouble concentrating or thinking. Patients call it "chemo brain." After several rounds of chemotherapy, you may feel a little foggy or forgetful. The changes tend to be subtle, and they might be more obvious to you than to the people around you. You may need to take a few extra steps to compensate, like making lists or giving yourself frequent reminders. Some cancer scientists think stimulant drugs may help to relieve the cognitive changes and fatigue, but more research is needed before any treatments are approved. In 2005, a small study presented at the annual meeting of the American Society of Clinical Oncology showed promising results with using the mild stimulant dexmethylphenidate (Focalin) to treat chemo brain. More studies are needed to determine whether this therapy should be offered to chemotherapy patients who feel their thinking is impaired.
- Nerve damage. Damage to your nerves -- called neuropathy -- can make it harder for you to control your body. You may feel extra clumsy and may notice tingling, numbness, or pain in your hands or feet. Some doctors may have you try B vitamins or the amino acid glutamine to protect your nerves. These side effects may or may not be reversible, so its really important for people to report these symptoms to their doctor right away. Sometimes the chemo has to be stopped or the dose reduced to minimize side effects.
- Pain. Nerve damage can be painful. It's important to tell your doctor about your pain; describing it can be the first step toward getting effective relief. It's also important to remember that new bouts of pain don't necessarily mean that your cancer is spreading. It could be that the pain is caused by your treatment, not the disease.
- A weakened immune system and high risk of infection. Chemotherapy drugs can damage bone marrow, your body's white blood cell factory. These cells are some of the most important workers in the immune system. If your white blood cell count gets too low (leukopenia), you'll be vulnerable to all sorts of infections. While you're being treated, you'll have to watch for signs of infection, especially fevers. Any temperature equal to or over 100.5 degrees F can be cause for concern.
After you've started chemotherapy, you'll have your blood tested on a regular basis -- perhaps even daily -- to see how well your white blood cells are holding up. If the numbers get dangerously low, you'll have to take a break from the chemo. Your doctor may also give you a shot of a medication such as pegfilgrastim (Neulasta) to give your white blood cells a boost.
- Heart trouble. Certain chemotherapy drugs, such as doxorubicin and daunorubicin, have the potential to damage the heart. Over one-third of the patients who take these drugs can develop heart failure. For that reason, your doctor may want to give your heart thorough checkups before and during treatment. Tell your doctor right away if you notice a change in your heart rhythm. You should also report possible signs of heart failure such as sudden weight gain or shortness of breath. The good news is that the standard treatments for heart failure -- including drugs such as beta blockers and ACE inhibitors -- can be very effective for treating chemotherapy-related heart trouble.
- Constipation or diarrhea. Be prepared to answer lots of questions about your bathroom habits. Doctors and nurses will want to make sure that you aren't having any trouble with constipation or diarrhea, two common side effects of chemotherapy and pain medicines. A change in medication or in lifestyle can often fix these problems.
- Kidney or urinary changes. Many chemo drugs eventually get processed by your liver and kidneys and leave your body in your urine. You might notice changes in urine color, blood in urine, or burning or pain while urinating. Some people feel the need to go more often or have trouble controlling their bladders. Most of these effects will go away after you stop chemo. (If you take doxorubicin (Adriamycin), don't be alarmed if your urine is pink or orange right after an infusion. The cause is the drug's bright red color and things will go back to normal quickly.)
- Sexual effects. With all the stress of cancer treatment, you may not be feeling very frisky. But there's another factor at work too -- chemo drugs can affect your hormones and sex drive. Luckily, this effect is temporary. Yeast infections are common among women on chemo, but they should stop bothering you after your treatment is finished.
- Infertility. Cancer drugs can damage the ovaries and testes, and in many cases the damage can be permanent. After age 30, it's also common for women to go into early menopause after chemo. If you plan to have children, ask your doctor for a referral to a fertility doctor to discuss your options before you start treatment. For both men and women who are sexually active it's important to use birth control while on chemo because the toxic drugs can cause birth defects.
- Long-term effects. In some cases, there can be long-term side effects from chemotherapy, including organ and nerve damage and blood in the urine. Sometimes another type of cancer can develop later on as a result of the chemotherapy. Children on chemo may have developmental delays as well. The particular effects will depend on the type of drugs you get, the dosage, and your own reaction to them.
How will I know if chemotherapy is working?
Your doctor has several ways to track the progress of your treatment. Imaging tests like CTs and MRIs can measure the size and locations of tumors. In some cases, you can tell that chemotherapy is working because your cancer-related symptoms start fading. Depending on the type of cancer, your doctor may also run regular blood tests to check for "markers," or proteins produced by cancer cells. A drop in your markers suggests that the chemo is working. But don't be too alarmed if your marker levels start to climb. More than anything, markers are a tool to help your doctor plan your treatment. A single number won't determine your health -- or your future.
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