How Does Chemotherapy Treat Cancer?


Chemotherapy is a type of treatment which involves the use of anti-cancer drugs that destroy cancer cells. It is also termed as ‘chemo’. It works by slowing or killing the growth of the cancer cells. Apart from other treatments such as surgery and radiation therapy, chemo works by circulating throughout the body, so that it may treat the cancer cells that may have spread to other areas far away from the original site.

Chemotherapy may cause some side effects to normal body tissues and the cells which grow and divide quickly such as hair (which always grows), skin and the lining of the digestive system (that uniformly revive themselves), bone tissues (which uniformly produce blood cells). As these tissues have actively dividing cells, the cells that get damaged by the chemotherapy may replace or repair the healthy cells. Once the treatment is over, most of the side effects disappear. The chemotherapy treatment is given through an injection or a drip intravenously (through the vein), or orally as tablets and capsules.

Benefits of Chemotherapy

The chemotherapy treatment is recommended by the doctors depending upon the type of cancer.

  • Cure cancer: Chemotherapy treatment is suggested to a person if there is a possibility to cure cancer. Curing means the cancer is destroyed and may not come back.
  • Control cancer: Another goal is cancer control if there is no possibility of the cure. Chemotherapy may also help to shrink or stop spreading and growing the cancer cells.
  • Ease the symptoms of cancer: It is also termed as palliative care. When the cancer is in the advanced stage, cancer may spread (from the original site to other parts of the body). The chemotherapy is used to shrink the tumor that may help to relieve the symptom such as pain or pressure.

The oncologist might choose different schedules and different combination of drugs depending upon the following factors such as:

  • Cancer type
  • Cancer stage
  • Patient’s age
  • Patient’s overall health
  • Previous cancer treatment was given
  • Health problem such as liver, heart, kidney disease etc

Dosage of Chemotherapy

The oncologist, depending upon the drug, will calculate the chemo doses precisely. They may prescribe the dose based on their person’s body weight in kg, the body surface area (BSA) (by calculating height and weight). In some cases the dosage of some drugs is adjusted for:

  • Elderly people
  • Obese person
  • People who have poor nutritional status
  • People who have already taken or currently taking other medicines
  • People who have low blood cell count
  • People who have liver or kidney disease

The specialists may suggest chemotherapy at a regular interval (cycles) in a dose of one or more drug for several days or months. Based on the type and stage of cancer, the number of cycles is decided.

In some cases, the chemotherapy might not cure cancer and is used along with other types of treatment. The specialist may suggest chemotherapy after surgery to destroy the remaining cancer cells. For instance, the specialist may recommend chemotherapy for breast cancer after the surgery to lower the risk of cancer. In some cases, the specialist may suggest chemotherapy, for relieving the symptoms of cancer, to control cancer and to live longer and better life.