^{Immunology and Oncology}

The genetic changes that contribute to cancer tend to affect three main types of genes - proto-oncogenes, tumour suppressor genes, and DNA repair genes. These changes are sometimes called “drivers” of cancer. Proto-oncogenes are involved in normal cell growth and division. However, when these genes are altered in certain ways or are more active than normal, they may become cancer-causing genes (or oncogenes) allowing cells to grow and survive when they should not. Tumour suppressor genes are also involved in controlling cell growth and division. Cells with certain alterations in tumour suppressor genes may divide in an uncontrolled manner. DNA repair genes are involved in fixing damaged DNA. Cells with mutations in these genes tend to develop additional mutations in other genes. Together, these mutations may cause the cells to become cancerous. The process by which cancer cells spread to other parts of the body is called metastasis. Metastatic cancer spreads from the part of the body where it originated (the primary site) to other parts of the body. A risk factor is anything that increases a person’s chances of developing a Tumor. Although factors often influence the development of a tumour, most do not directly cause it. Some people with several risk factors never develop a tumour, while others with no known risk factors do. Some risk factors are as Age, Gender, Race/Ethnicity, Family history, Immune system suppression, arsenic exposure. Generally, the cause of Cancer is unknown. People who have one of the rare family syndromes have a higher risk of developing Tumors.