Each year 14.1 million people get the diagnosis of cancer. During a lifetime nearly every second man and every third women are cancer patients. The classical ways of cancer treatment are the resection of the tumor itself, as well as chemotherapy and radiation therapy. Often patients are treated by a combination of this aggressive procedures. 

A first step in understanding the development of cancer in patients organs is to unmask the identity of the tumor by deciphering the tumor genome and by examining where the tumor has its origin, e.g. if it is caused by a viral infection like liver cancer fostered by hepatitis B virus. 

In healthy people the immune system recognizes the difference between physiological body cells and cells not belonging to the body like pathogens (bacteria, viruses, ...). If the actions of the immune system are too weak, people suffer from permanent infections. If the immune system reacts to excessive, the body begins to fight against its own cells and autoimmune disorders occur. Right in the middle of this balanced reactions of the immune system tumors are able to escape from the immune reaction. Tumor cells show no signs of cells not belonging to the body and will therefore not be recognized by the immune system as cells which has to be eliminated; a tumor begins to grow and in the worst case to metastasise. Scientists think that many cells carrying tumor-triggering-mutations are eliminated by reactions of the immune system.