There are currently multiple choices for cancer treatment. Surgery and radiotherapy are used as local therapies and mainly to treat early stages of the disease whereas chemotherapy is a systemic treatment used basically when the disease has spread. Nevertheless, these three combined therapeutic modalities are increasingly being applied. The main systemic treatment is chemotherapy and its aim is to eliminate remaining cancer cells in the body. Thus, medication has to enter the bloodstream and be distributed to the tissues. However, not all drugs used to treat cancer are cytostatic (chemotherapy). Others such as hormone therapy, immunotherapy and drugs directed against molecular targets are available.