The word `chemotherapy' means `drug treatment'. Chemotherapy is the use of anti-cancer (cytotoxic) drugs to destroy cancer cells (including leukaemias and lymphomas). It may be used alone to treat some types of cancer. Sometimes it can be used together with other types of treatment such as surgery, radiotherapy, immunotherapy, or a combination of both.
Cells in the body constantly grow and divide to replace old and damaged cells. Normally, cells divide and reproduce in an orderly manner. In cancer, cells keep dividing randomly, without proper control, forming a lump (which is called a tumour). In leukaemia, too many white blood cells are produced.
Many chemotherapy drugs act against cancer cells by interacting with the DNA or RNA, or the genetic makeup, of the cancer cell.
Unfortunately, chemotherapy drugs can also affect some of the normal cells in the body. However, damage to the normal is usually temporary and most side effects will disappear once the treatment is over.
Common side effects of chemotherapy may include: nausea and vomiting, hair loss, anaemia, reduced ability of blood to clot, mouth sores and increased likelihood of developing infections.
Four of the chemotherapy drug types that act directly to impair the DNA in cancer cells are the DNA-damaging agents; antitumour antibiotics; antimetabolites; and DNA-repair enzyme inhibitors.
Chemotherapy drugs are often given in combination with each other, and can be given in different ways. The four most common methods are: intravenous, oral, intramuscular, and intrathecal. The method is based on the actual disease diagnosed and the agent's effectiveness.
Source : The Hindu