Cancer comprises numerous different conditions characterized by uncontrolled cell growth.  There are three general solid tumor classifications: (1) carcinomas, cancers originating in the epithelial tissue; (2) sarcomas, cancers originating in connective tissue and muscle; and (3) gliomas, cancers originating in nerve tissue.  
 
There are also three types of hematological (liquid) tumors: myelomas
(originating in plasma cells), leukemias (originating in bone marrow), and lymphomas (originating in the lymphatic system).  
 
The most common types of cancers are lung, breast, colorectal and prostate, which together account for about 43% of new cases worldwide and half of new cases in the U.S.
Worldwide, more than 14 million new cases of cancer are diagnosed each year and this number is expected to increase to 24 million by 2035.[]  The American Cancer Society estimates that more than 13 million people are living with cancer in the U.S, with an additional 1.6 million people newly diagnosed each year.