What is chemotherapy?

Chemotherap (chemo) is a type of cancer treatment that uses drugs to kill cancer cells. It uses powerful medications to kill fast-growing cells in your body, like cancer cells. It can be used on its own or with other treatments. There are many different kinds of chemotherapy drugs.

How you receive chemo depends on the type of cancer and what stage it is, whether you have had previous cancer treatments and your health. Chemotherapy is most often administered through an IV through a vein in your hand or arm. It may also be given in a pill, shot, cream or given directly to one area of the body. 

Chemotherapy can be given in cycles or continuously. A cycle is a period of chemotherapy treatment followed by a period of rest. The rest period gives your body a chance to recover. A medical oncologist will determine how often you will receive chemotherapy treatments based upon what medications you will receive, the characteristics of your cancer, as well as, how your body reacts after each treatment.

Chemo may be used alone for some types of cancer. Or it may be given with other treatments, such as radiation or surgery. Chemo may also be used along with other cancer medicine treatments, such as targeted therapy,  hormone therapy or immunotherapy. Often a combination of chemo medicines is used to treat a certain type of cancer. These combinations are given in a certain order.

Treatment Overview

When is chemotherapy used?

Your health care provider may suggest chemo for any of these reasons:

  • Alone, as the sole treatment. Some cancers are treated right away with chemo only.
  • Before surgery or radiation. It helps to shrink the tumor so that it's smaller and easier to take out or treat with radiation.
  • At the same time as radiation. This is called concurrent chemoradiation. The chemo helps the radiation work more effectively.
  • After surgery or radiation. It helps keep any cancer cells that are left from growing and spreading. Whether your health care provider suggests it depends on the tumor's size, if it has spread and other factors.
  • When the cancer has spread to other parts of your body. Because chemo travels all over the body to kill cancer cells, it can be used to kill cancer cells that have spread.
  • To ease problems caused by the cancer. Some problems could include tumors pressing on tissue that could cause pain or obstruction. This is called supportive or palliative care.

How is chemotherapy given?

Chemo can be given in any of these ways:

  • As a pill or liquid you swallow (orally)
  • As a shot (injection) into the muscle or fat tissue
  • Directly into the blood (by IV or intravenously)
  • Applied to the skin (topically)
  • Directly into a body cavity, such as the belly (intracavitary chemo)
  • Into your spinal canal to reach your brain and spinal cord (intrathecal or IT)
  • Directly into the bladder for a short time (intravesical)
  • Into a main artery that "feeds" the tumor (intra-arterial)
  • Through a needle into the tumor (intralesional)

Chemo is usually given in cycles to reduce the damage to healthy cells. Each cycle includes a time of treatment and a time of rest with no treatment. Cycles allow the medicines to kill more cancer cells because not all of the cells are dividing at the same time. The rest period gives the healthy cells in your body time to recover and heal. Chemo may be given daily, weekly, every few weeks or monthly.

This may be a hospital, clinic or provider's office. Patients receiving chemotherapy will be watched closely for reactions during treatments. Since each treatment session may take a while, you’re encouraged to bring things that are comforting, such as music to listen to. It's also advised to bring something to help pass the time, such as a laptop or a book. Since it's hard to predict how you will feel after chemotherapy, it's important to have someone drive you to and from the treatment the first few times.

Benefits and Risks

What are the risks of chemotherapy?

Chemo can work well to treat certain cancers. But chemotherapy medicines travel to all parts of the body, not just the cancer cells. So healthy cells can be damaged, too. This can lead to side effects during treatment. Knowing what these side effects are and that they can happen can help you and your caregivers prepare for and manage them. 

Side Effects

What are common side effects of chemotherapy?

Many different kinds of chemo medicines are used to treat cancer. Nearly all of them cause side effects.

Side effects may happen just after treatment (in minutes, hours, days or weeks). Or they may happen months or even years later after chemo has been given. Side effects may be severe, mild or absent. Each person's medical history, overall health and diagnosis is different. So is the reaction to treatment.

Side effects depend on the chemo medicines used, dose and the combinations used. Before treatment starts, talk with your cancer care team about the possible side effects of your treatment. Ask about each medicine's side effects. Get written information on each medicine you're getting so you know what to watch for and what to report to your health care provider.

Some of the most common short-term side effects include:

  • Extreme tiredness (fatigue)
  • Increased risk for infection
  • Easy bruising and bleeding
  • Mouth and throat sores
  • Nausea and vomiting
  • Diarrhea
  • Constipation
  • Hair loss
  • Skin and nail changes
  • Nerve damage , such as numbness or tingling usually in your feet and sometimes hands
  • No desire to eat
  • Weight gain or loss
  • Changes in your memory or thinking

Possible long-term side effects include:

  • Not able to have children (infertility)
  • Memory or thinking changes
  • Damage to certain organs, such as your heart, bladder, or lungs
  • Increased risk for other kinds of cancer
  • Nerve damage

Many of the short-term side effects can be controlled or even prevented. Most get better during the rest part of the chemo cycle. They often go away over time after treatment is done.

Management & Support

Also talk with your healthcare providers about what problems to look for and when to call them. Make sure you know what number to call with questions. Is there a different number for evenings, holidays, and weekends?

There's no way to tell if you will have side effects from chemo, or how bad they will be. Knowing what to watch for and what to do if you have problems, is a good way to be prepared. It may be helpful to keep a diary of your side effects. Write down any physical, thinking, and emotional changes. A written list will make it easier for you to work with your healthcare team to make a plan to manage your side effects. It will also help you remember your questions when you go to your appointments. 

Cancer treatment is easier to cope with when you have support. Your health care team is there to be a support to you in all aspects. 


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