Cancer

Cancer refers to a malignant process of the growth of a certain type of cells in vertebrates: epithelial cells. Although this technical description is strictly accurate, the word is often used, even by physicians, to include all the diseases directly caused by malignant tumors and cells. For example, malignant tumors called sarcomas arise from abnormal muscle cells, and since these tissues are derived from mesothelium rather than from epithelium, that word sarcoma is used rather than cancer. Still, Cancer Centers and specialists include treatment of sarcoma in practice, despite the fact that these tumors are not strictly cancers as far as medical terminology of tumors go. In other words, all types of malignant tumors are sometimes refered to as cancers. This introductory article will give a brief description of what a malignancy is, and how cells are thought to become malignant. That understanding is important as a basis to understand the medical and surgical treatment of cancers, and also in their prevention.