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Chemotherapy in cancer treatment

​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​Chemotherapy is one of the major treatments your doctor uses to fight cancer. 

More than 100 drugs are currently used to treat cancer - alone or in combination with other drugs or treatments.

Chemotherapy uses drugs to:

  • Shrink cancer tumors
  • Keep tumors from spreading
  • Kill cancer cells that have spread to other areas of the body
  • Relieve symptoms related to cancer

Types of chemotherapy

  • Biologic therapy (immunotherapy): A form of cancer treatment that uses the body's immune system to fight cancer. It is generally used together with other cancer treatments to improve treatment effectiveness or to decrease side effects.
  • Hormone therapy: Some types of cancer can only grow and spread if natural chemicals in the body, called hormones, are present.
    Hormone therapy fights cancer by changing the amounts of hormones in the body. This is most commonly used to treat cancers of the breast, prostate and reproductive system.
  • Monoclonal antibodies: Laboratory-made drugs that attach to proteins on the surface of cancer cells. When they attach, they stop the protein from doing its job, such as making cancer cells grow.
    ​​​​Monoclonal antibodies can be used alone or in combination with other therapies.
  • Targeted therapies: Drugs that selectively kill only cancer cells, decreasing side effects.
  • Anti-angiogenesis drugs: The formation of new blood vessels feeding tumors is called angiogenesis. Anti-angiogenesis drugs cut off a tumor's blood supply so the tumor starves and cannot grow.

How Is Chemotherapy Given?

Chemotherapy is most commonly given as an injection but can also be given orally as a liquid or pill.

How Long Does Chemotherapy Treatment Last?

Your treatment may be as short as 30 minutes or as long as 8 hours. Most chemotherapy treatments last 1-3 hours.

How Often Do Chemotherapy Treatments Occur?

Chemotherapy treatment is given in cycles, which usually consist of days on treatment followed by days off treatment (treatment cycle). Cycled chemotherapy treatment helps decrease the harm to healthy cells and allows the drugs to kill more cancer cells. ​​​