How Does Chemotherapy Kill Cancer?

There are a plethora of options when treating cancer, all of them with distinct advantages and disadvantages. Although chemotherapy is well known for its side effects, it remains one of the most effective tools for defeating cancer cells in the body, especially when used in conjunction with other treatments.

Basics

• Chemotherapy is the process of using drugs to treat a disease, and it works against cancer by damaging cells in the body that are undergoing the process of division. The cancer-fighting drugs can be injected directly into the bloodstream, or taken as a tablet or capsule. Once in the bloodstream, the chemotherapy drugs travel around the body in order to damage and kill the cancer where it has spread.

Cancer Cells vs. Normal Cells

• Chemotherapy gains its advantage over cancer cells because it attacks cells that are dividing. Cancer cells are constantly splitting and growing, especially in the initial stages of the cancer. Chemotherapy drugs disrupt the process of dividing by attacking the control center of division: the nucleus. Chemotherapy drugs can damage the genes that are copied within the nucleus during division, or they can damage cells when they are physically splitting. Most normal body cells do not split often, and when they do it is in a more controlled way than cancer cells. Chemotherapy is especially effective against rapidly dividing cells.

Effectiveness

• The effectiveness of the chemotherapy depends almost entirely on the type of cancer. It can be a very effective deterrent or even cure with Hodgkin's lymphoma or testicular cancer. In other cases, the chemotherapy can be used in conjunction with other treatments, like surgery, to stop the reemergence of cancer cells. This method is effective against breast or bowel cancer.

Remission

• Chemotherapy is effective at achieving the remission of cancer cells. Remission is not strictly a cure; it occurs when there is little proof of the existence of cancer cells in the body, and there is a small chance of its reemergence. The more time that passes, the less chance the cancer will come back. Partial remission occurs when the cancer cells can still be found within the body, but chemotherapy has stopped the cells from growing and splitting. Complete remission occurs when the cancer is not found at all.

Side Effects

• Because chemotherapy does disrupt the process of cell division, it unfortunately can also disrupt cells in the body that are constantly in division. For example, the bone marrow, hair follicles and skin are constantly dividing, so the chemotherapy can cause their division processes to stop. Fortunately, the damage does not last after the chemotherapy has run its course, and normal cells can replace the damaged cells after treatment.