Chemotherapy is a type of cancer treatment that uses one or more anti-cancer drugs as part of a standardized chemotherapy regimen. A drug treatment that uses powerful chemicals to kill fast-growing cancer cells in your body and is most often used to treat cancer, since cancer cells grow and multiply much more quickly than most cells in the body. Many different chemotherapy drugs are available. Chemotherapy may be given with curative intent, or it may aim to prolong life or to reduce symptoms. The aim is to kill cancer cells while doing the least possible damage to normal cells.
Chemotherapy travels through the bloodstream to stop or slow the growth of rapidly dividing cancer cells. Cancer cells exposed to chemotherapy medication are less likely to grow back than non-treated cancer cells.
Chemotherapy can also affect healthy cells. The effects of chemotherapy on healthy cells cause the side-effects. Healthy cells however have the potential to grow again.
How Chemotherapy is Used
Doctors use chemotherapy in different ways at different times:
- Before surgery or radiation therapy to shrink tumors. This is called neoadjuvant chemotherapy.
- After surgery or radiation therapy to destroy any remaining cancer cells. This is called adjuvant chemotherapy.
- As the only treatment. For example, to treat cancers such as leukemia and lymphoma.
- For cancer that comes back after treatment, called recurrent cancer.
- For cancer that has spread to other parts of the body, called metastatic cancer.
The Goals of Chemotherapy
The goals of chemotherapy depend on the type of cancer and how far it has spread. Sometimes, the goal of treatment is to get rid of all cancer and keep it from coming back. If this is not possible, you might receive chemotherapy to delay or slow cancer growth. Delaying or slowing cancer growth with chemotherapy also helps manage symptoms caused by cancer.
There are many drugs available to treat cancer. You may receive a combination of drugs because this sometimes works better than only 1 drug. The drugs, dose, and treatment schedule depend on many factors – the type of cancer, tumor size, its location, and if or where it has spread, your age, general health, and how well you can cope with certain side effects. You may receive your chemotherapy at the clinic, doctor’s office, or hospital.
Chemotherapy is often given for a specific time, such as 6 months or a year. Or you might receive chemotherapy for as long as it works. Side effects from many drugs are too severe to give treatment every day. Doctors usually give these drugs with breaks, so you have time to rest and recover before the next treatment. This lets your healthy cells heal.
Chemotherapy may be given in several different ways:
- Intravenous (IV) chemotherapy. Many drugs require injection directly into a vein.
- Oral chemotherapy. You can take some drugs by mouth.
- Injected chemotherapy. This is when you receive chemotherapy as a shot.
- Chemotherapy into an artery. This is injected into an artery to go directly to cancer.
- Chemotherapy into the peritoneum or abdomen. For some cancers, medication might be placed directly in your abdomen. The peritoneum covers the surface of the inside of the abdomen and surrounds the intestines, liver, and stomach.
- Topical chemotherapy. Some types of chemotherapy as a cream to put on your skin.