Cancer - a disease that everyone knows and yet leaves so many questions unanswered.Although cancer can be diagnosed very soon by early detection and preventive examination, the number of tumors increases. The Reasons for this effect are different factors such as tobacco smoke, physical inactivity as well as the western lifestyle and the genetic predisposition. Physical exercise and sports are phenomenons that are rooted in the lifestyle of people, for thousands of years. They affect not only the quality of life of cancer patients on several levels, but even those of the rest of the population. Sports and physical exercise are strengthen the health and the immune system and convey a sense of confidence in your own body. Even so, coping stategies are built, to fight but also to accept certain limitations. The specific relationship between exercise, sport and cancer was examined more detailed in numerous scientific studies over the last decade. According to these, positive effects for tumor patients could be gained: it improves the performance and the strength of the muscle, reduces undesirable side effects after surgery or chemotherapy, relieves chronic fatigue and opposes the fear. Consequently, physical exercise and sports are recommended and applied during the treatment of various cancers. Prostatic cancer and breast cancer are the most common cancer types of men and women. Eventhough a very good chance of recovery is reported.The following work will discuss the different aspects of the "social disease" cancer. The relation of breast cancer and physical exercise as well as sports therapy in the acute phase and after, are listed in more detail.