The purpose of Chemotherapy in the Medicine/Health Field

The purpose of chemotherapy depends on the type, stage, and location of the tumor. But generally, chemotherapy is used to shrink or kill a tumor or any disease that is able to spread through the body. Another purpose of chemo is to stop the growth of the cancer cells for a period of time in order for the rest of the cancer to be removed through surgery. If the elimination of cancer can not be completed with the use of chemotherapy, then it could be used along with a different type of treatment for the destruction of the cancer cells throughout the body.

This diagram shows the differences between cancer cells and normal cells

How does chemotherapy work?

Chemotherapy consists of a wide variety of drugs. These drugs are inserted into the body using injections or pills which each have a specific function to help destroy the cancer by stopping the growth of the cells. Because of the rapid pace that cancer cells divide, they are most sensitive to these drugs and cannot fight them off. Chemotherapy stops the reproduction of cancerous cells so that they will decrease and should eventually eliminate the cancer. 

The drugs could affect the functions of normal cells because some normal cells do divide a lot faster than other cells such as the skin cells, stomach, bladder, intestines. When normal cells are affected, side effects occur. Blood cells are the most affected cells from chemotherapy and since these cells fight infections, carry oxygen through the body, and assist in blood clotting, a decrease in these cells could cause anemia, neutropenia, thrombocytopenia, hair loss, and memory changes.

Anemia is a condition where the body has a shortage of healthy red blood cells. When having anemia, you should have blood transfusions to increase the amount of red blood cells.  Neutropenia is where you have a decrease in white blood cells. White blood cells are needed to fight off bacteria and infections. Thrombocytopenia is a decrease in platelets, therefore patients should avoid any activities which could result in blood loss or internal bleeding. Hair loss occurs from the drugs having an effect on the fast growing cells in the hair roots. Memory loss is caused by the medications given, by stress, or other health problems. Patients using the process of chemotherapy must watch for different symptoms of these side effects for they could result in life-threatening issues.

Drugs used in Chemotherapy

The word chemotherapy is capable of being divided into two parts, the word chemo being the prefix and therapy being the suffix. The word chemo refers to chemicals, therefore chemotherapy means to treat a specific disease using chemicals, in this case, cancer. Chemicals are used to stop the growth of cancer cells within the body. The chemicals used could be put into four different categories: alkylating agents, anti-metabolites, vinca alkaloids, cytotoxic antibiotics. Alkylating agents are used to attack the DNA within the cells. During the synthesis stage in mitosis, anti-metabolites would block the growth of cells. During the metaphase stage in mitosis, the plant(vinca) alkaloids help stop the formation of mitotic spindles which prevents the cell from dividing. During the interphase stage, cytotoxic antibiotics help stop the duplication of the DNA. The chemicals in these four categories all help assist in stopping cell division.

This shows the different stages that cancer or tumors go through and spread through organs

These are examples of drugs used in the chemotherapy process