Cancer

Cancer describes a group of diseases where malignant growths, or tumors, are caused by excessive division of the body's cells. The cells within a body infected by cancer never die, rather, more cells continue to be created, leading to abnormal cells. These cells can actually grow into tissue (tumors) and invade the body's internal organs. This process results from DNA damage within the cells. Typically, DNA damage is repaired by the body naturally; however, if left unrepaired, this type of excessive cell division can occur. There are many different types of cancer, including lung, breast, and skin cancer, and each acts differently. Chemotherapy is the most widely known cancer treatment, designed to kill cancer cells; however, while certain forms of cancer are treatable, others currently are not.