Cancer is caused by the uncontrolled growth of abnormal cells in the human body.
Cancer cells do not grow and die in an orderly fashion. Rather, they continue to grow and divide, and replace normal, healthy cells.
Abnormal cells are formed when Deoxyribonucleic Acid (DNA) is damaged and not repaired by the body. DNA can be damaged through:
- Exposure to environmental factors such as ultraviolet light, chemicals or cigarette smoke
- Genetic factors – some cancers appear to be inherited
- Exposure to certain viruses – for example, some forms of cervical cancer have been linked to exposure to the human papilloma virus (HPV).
Types of cancer
Cancer is not one disease, but many different types of disease. Prostate cancer is not the same as breast cancer, which is not the same as bladder cancer. Therefore, each cancer may respond differently to various forms of treatment.
Not all cancers behave alike. Some cancers form solid masses, called tumors. Other cancers form in the blood and circulate to other organs.
Some tumor-forming cancer cells can remain within one organ or body part, while others may "metastasize" and spread to other organs.
What will happen to me?
How cancer affects you depends on a number of factors. These factors can include:
- Cancer type
- Cancer location in your body
- How far the cancer has spread
- Your overall health at the time of diagnosis / treatment
- How the cancer responds to treatment