Cancer is the general name for more than 100 diseases characterized by uncontrolled cell growth. Whereas normal cells follow a path of growth, division and death, cancer cells continue to divide when new cells are not needed. Uncontrolled cell growth leads to a mass or growth of tissue that is called a tumor (except in the cancers known as leukemia where cancer interferes with normal blood function by abnormal cell division in the blood stream).
Not all tumors are cancerous. Benign tumors are not cancerous. They can be removed, and in most cases do not come back. Malignant tumors are cancerous. These malignant cancer cells can enter the bloodstream and spread throughout the body invading and destroying healthy tissue. This spreading from one part of the body to another is called metastasis.
Cancer is named for the place where it started. Different types of cancer behave differently, so cancer that has metastasized is still named for its place of origin. For example, if breast cancer spreads to the liver, it is called "metastatic breast cancer," not liver cancer.
Cancer can be attributed to environmental and genetic factors. Environmental factors that contribute to cancer include tobacco, diet and obesity, infections, radiation, stress, lack of physical activity, and environmental pollutants. The majority of cancers are not hereditary. Less than 0.3% of the population are carriers of a genetic mutation which has a large effect on cancer risk. An example would be an inherited mutation in the BRCA1 and BRCA2 genes. Mutations in these genes may indicate a higher risk for development of breast and ovarian cancer.
If a physical exam produces signs or symptoms that cause a physician to suspect cancer, a combination of biopsies, labs, imaging and genetic tests may be ordered.
Cancer is treated with surgery, radiation, chemotherapy, biologic therapies, hormone therapies or transplant options such the transplantation of bone marrow. A team of specialists including medical oncologists, surgeons, radiation oncologists and others will work together to determine what treatment or combination of treatments will be best for you individually.