The Basics Of Cancer* By Aoife Rafferty* Catherine Quaile* Kayleigh Powderly*

*What Is Cancer?  Cancer is a group of many related diseases. All cancers begin in cells, the building blocks that make up tissues.  The study of cancer is called oncology.  Normally, cells grow and divide to form new cells as the body needs them. When cells die, new cells take their place. Sometimes this process goes wrong and new cells form when the body doesn't need them, and old cells don't die when they should.  The extra cells form a mass of tissue, called a growth or tumor. Tumors can either be malignant or benign.  Malignant type tumors are those which can spread (metastasize) and may be life threatening. Benign tumors do not spread & are rarely life threatening.  Cancer causes about 13% of all deaths.

Formation Of Cancer Cells* A normal, healthy cell (Aerobic state). From aerobic to anaerobic state – forming the cancer cell

 The original tumor is called the primary cancer or primary tumor. Metastasis  Metastasis means the spread of cancer. Cancer cells can spread to almost any part of the body.  It is not possible to have a metastatic tumor without having a primary tumor. In most cases, when a metastatic tumor is found first, the primary tumor can be found. How tumors metastasise.

How Cancer Cells Are Formed*  The transformation of a normal cell into a cancer cell can occur when the genetic material (deoxyribonucleic acid-DNA) of a cell is altered or mutated.  The cell's genes are converted into oncogenes (cancer- causing genes).Tumor suppressor genes are then inactivated in cancer cells, resulting in the loss of control over the cell cycle  A tumor is the result of multiple gene mutations within a single cell.  Years before a tumor forms, a cell can become weakened by various factors, making it more susceptible to later transformation into a cancer cell.

 Carcinogen: A substance capable of causing cancer.  One of the most carcinogenic substances is tobacco smoke. Other carcinogens include certain chemicals, the sun's ultraviolet light and radiation. Genetic factors - such as chromosomal abnormalities or the inheritance of faulty genes from a parent - can make people more likely to develop certain cancers. For instance, people with Down Syndrome, a chromosomal abnormality, are susceptible to leukemia. Chromosomes are found in the cell nucleus, are made of DNA and DNA proteins(which control the DNA’s functions). Sections of chromosomes are called genes

Inheritance & Familial Cancer*  Some people are born with a fault in one of their genes.  A gene is a region of DNA that controls a hereditary characteristic.  This does not mean that they will ever actually develop cancer, but it does mean that fewer things need to go wrong with the rest of their DNA for it to develop.

Radiation Exposure & Cancer. Ionizing radiation consists of high-energy waves that are able to penetrate cells. DNA is very sensitive to ionizing radiation. Ionizing radiation can lead to a mutation(change) in a cell's DNA. Does ionizing radiation cause cancer? It has been known to cause cancer in different species of animals and in the human body. Many years may elapse between the radiation exposure and the appearance of the cancer.

Treatment*  Surgery to remove tumors  Radiation to slow tumor growth  Chemotherapy - Used to treat cancers that have spread to other parts of the body  Immunotherapy - Antibodies that boost the immune system and can find & destroy abnormal cells.

Surgery: The goal of the surgery can be either the removal of only the tumor or the entire organ.

Radiation Therapy *  The use of ionizing radiation to kill cancer cells and shrink tumors.  Injures or destroys cells in the area being treated by damaging their genetic material, making it impossible for these cells to continue to grow and divide.  The goal is to damage as many cancer cells as possible, while limiting harm to nearby healthy tissue.

Chemotherapy* The treatment of cancer with drugs that can destroy cancer cells. Most forms of chemotherapy target all rapidly dividing cells and are not specific for cancer cells, hence, chemotherapy has the potential to harm healthy tissue, especially those tissues that have a high replacement rate (e.g. intestinal lining). These cells usually repair themselves after chemotherapy.