Cancer Essay Example | Topics and Well Written Essays - 1000 words - 4

Cancer - Essay Example Cancer was initially completely untreatable. With medical advances, such as autopsies, anesthesia and the microscope, scientific oncology was born. Finally, in the eighteenth century, the understanding of molecular epidemiology led to the modern study and treatment of cancer (American Cancer Society). The origin of cancer lies in abnormal cell division. In normal cell division, new cells are produced as and when needed for a healthy body and when cells become old or damaged, they die and are replaced with new cells. Sometimes, there is damage to the cell DNA, the basic material in genes. These defective genes may be caused by mutations or may also be inherited. Instead of dying, these damaged cells lead to the formation of groups of malignant clones, or duplicates of the abnormal cells. These groups form a mass of tissue called a  tumor. A benign tumor is harmless and its cells do not spread to other parts of the body. A malignant tumor is cancerous. Its cells invade adjoining tissues and spread to other parts of the body in a process called metastasis. Cancer cells spread through the blood and lymph systems. There are more than 100 different types of cancer. The main types of cancer are: Carcinoma - cancer which originates in the skin or the lining of tissues; Sarcoma – cancer which begins in in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue; Leukemia – cancer in the blood and bone marrow; Lymphoma and myeloma  - cancers that begin in the cells of the  immune system; Central nervous system cancers  - cancers that begin in the tissues of the brain and spinal cord (National Cancer Institute). The types of cancer are named according to the name of the organ or tissue in which they originate. The main types are: Adenoid Cystic Carcinoma, Adrenal Gland Tumor, Amyloidosis (blood), Anal Cancer, Appendix Cancer, Astrocytoma