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Understanding Chemotherapy

Man in outpatient clinic having chemotherapy infusion.
Chemotherapy is often given in an outpatient setting.
Chemotherapy (“chemo”) is a treatment for cancer. Chemo can be a single medication. Or, it can be a combination of medicines. When used alone or along with surgery or radiation therapy, it can often shrink a tumor or prevent its spread.

How chemotherapy works

Chemotherapy kills cells that grow quickly.  Cancer cells can be fast growing cells; but many healthy cells grow fast, too.  Fast growing cells of the mouth, stomach lining, bone marrow, skin and hair are able to grow back, but cancer cells that die, are not.  That is why side effects such as hair loss, nausea, and low blood cell counts resolve with time.  Usually, chemotherapy is given in "cycles" of treatment.  A "cycle" is the time from one cancer treatment to the next.  For example, if a treatment is given 2 weeks in a row, and then one week off, it is referred to as a 3 week cycle.  If a treatment is given once every 3 week, it is referred to as a 3 week cycle, too.  Time between treatments (during the cycle) is necessary to let normal cell recover before the next treatment.

The goals of chemotherapy

Chemo can kill cancer cells. As a result, it may do the following:

  • Shrink cancer before surgery (neoadjuvent care)

  • Rid the body of cancer cells that remain after surgery (adjuvent care)

  • Reduce symptoms (such as pain) (palliative care)

  • Control cancer for a period of time (palliative care)

  • Cause remission (no evidence of the disease on medical testing)

  • Cure cancer (no evidence of the disease years after treatment)

Side effects of chemotherapy

When healthy cells are damaged, side effects may develop including:

  • Nausea and vomiting

  • Hair loss

  • Anemia (low red blood cell count)

  • Infections

  • Bleeding

  • Mouth and throat sores

  • Skin changes (dry skin, itching, acne)

  • Lack of interest in sex

  • Trouble remembering and concentrating

  • Stress and depression

Long-term risks and complications

There are some long-term risks with chemo. But the benefits usually outweigh the risks. Risks depend on the type of chemo used. Some possible long-term risks include:

  • Infertility

  • Damage to certain organs, such as the heart, kidneys, liver, or lungs

  • Lasting nerve damage

  • Another cancer forming at a later time

© 2000-2018 The StayWell Company, LLC. 800 Township Line Road, Yardley, PA 19067. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.