Since the mutations of a normal cell that lead to a malignancy, involves changes in the structure and function of the cells, it could be assumed that the immune system has recognized some of these changes as antigenic determinates that should be responded against. For many years, investigators tried to distinguish between cancer patients and healthy population by the difference in specific autoantibodies level. In the healthy population, a baseline of the amount of autoantibodies was determined, and the patient population had to have a statistically significant higher level of autoantibodies. The presence of autoantibodies in all population in different levels made it very difficult to find these specifically discriminating antibodies. To date, no specific autoantibody is distinguishing solely between healthy and cancer patients (as opposed to autoimmune diseases, where specific autoantibodies can be found in very high levels in patients only).