What is chemotherapy?

Chemotherapy is a type of treatment for cancer that uses medications. Cancer is an abnormal growth of cells. Normally, old or damaged cells in the body will stop dividing and die. Healthy young cells replace these cells. Cancer occurs when old or damaged cells divide and multiply uncontrollably. Cancer cells rapidly reproduce even when your body signals them to stop.

Chemotherapy works by slowing or stopping these rapidly growing cells. The goal of chemotherapy can be to cure cancer, control cancer, or relieve the symptoms of cancer.

Chemotherapy, sometimes called chemo, is only one method to treat cancer. You may have other treatment options. Consider getting a second opinion about all of your treatment choices before having chemotherapy.

Types of chemotherapy

The types of chemotherapy include:

  • Regional chemotherapy affects a specific area of your body instead of your whole body. Regional chemotherapy targets a tumor or tumors contained in one area. It can also help decrease side effects of a large tumor, such as a tumor that presses on another body part causing pain.
  • Systemic chemotherapy affects your entire body or system. It targets cancer cells that may have spread throughout different areas of your body.

Other procedures that may be performed

Doctors sometimes prescribe chemotherapy by itself to treat certain cancers. Your doctor may also prescribe one or more other treatments including:

  • Biological therapy (immunotherapy) boosts or stimulates your body’s immune system to help fight cancer. 
  • Hormonal therapy blocks the effects of hormones that stimulate growth of certain cancers. In doing this, hormonal therapy deprives cancer cells of what they need to grow. Examples of cancers treated by hormonal therapy include certain breast cancers and prostate cancers.
  • Laser therapy removes tumors and treats cancer symptoms with a laser.
  • Photodynamic therapy combines special drugs with specific wavelengths of light. The drug, called a photosensitizer, is injected into your tumor and exposed to the light. The light produces a reaction that kills cancer cells when it hits the drug.
  • Radiation therapy uses x-ray beams or other forms of radiation to kill cancer cells. It targets tumors and localized cancer cells. Newer technologies allow doctors to precisely target tumors and minimize damage to nearby healthy cells.
  • Surgery removes cancerous tumors and precancerous tissues.

Why is chemotherapy used? 

Chemotherapy treats many types of cancer. Your doctor may use chemotherapy as:

  • Adjuvant chemotherapy, to destroy cancer cells that may be left after surgery or radiation therapy
  • Concomitant chemotherapy, to work together with surgery or radiation therapy and help them work better
  • Neo-adjuvant chemotherapy, to help shrink tumors before surgery or radiation therapy
  • Relief of symptoms caused by tumors or cancer cells, such as pain or bleeding
  • Treatment for recurrent or metastatic cancers. Recurrent cancers are cancers that come back after being treated. Metastatic cancers are cancers that have spread to other areas of the body.

Who performs chemotherapy?

Chemotherapy is given by various healthcare professionals, depending on the type of cancer and chemotherapy. Specially trained oncology nurses often administer injections and intravenous chemotherapy.  You may be able to give yourself oral or topical chemotherapy at home. 

Doctors administer some types of chemotherapy, such as chemotherapy that is injected directly into a tumor. Doctors who administer or lead care teams that give and monitor chemotherapy include:

  • Gynecological oncologists are obstetrician-gynecologists (Ob/Gyns) who specialize in diagnosing and treating cancer of the female reproductive system, such as ovarian or cervical cancer.
  • Hematologists are internal medicine doctors who specialize in diagnosing and treating blood disorders.
  • Medical oncologists are internal medicine doctors who specialize in diagnosing cancer and treating it with chemotherapy and other non-surgical treatments.
  • Pediatric hematologist-oncologists are pediatricians who specialize in diagnosing and treating blood disorders and cancer in children.  
  • Surgical oncologists are surgeons who specialize in treating patients with cancerous and noncancerous (benign) tumors with surgery and other treatments.