Cancer
Any of a broad group of malignant neoplasms which are either carcinomas which have their origin in epithelial tissues or sarcomas which develop from connective tissues and those structures which had their origin in mesodermal tissues (the muscular, skeletal, circulatory, lymphatic and urogenital systems and the linings of body cavities). Cancer is invasive and tends to metastasize to new sites spreading directly into surrounding tissues or through the lymphatic or circulatory systems.