This type of prevention involves the complete removal of both breasts and all breast tissue. By having this operation individuals are able to completely eliminate the risk of having breast cancer. In most cases this procedure is only done on women who have many members of their family (mothers, grandmothers, aunts) that have been diagnosed or died from breast cancer. In such instances there is usually a genetic reason why members of the same family have acquired breast cancer or other types of cancer. It is actually a genetic defect in which the proto-oncogene mutates and becomes an oncogene. Basically the job of the proto-oncogene is to create the code for the protein that controls cell division. When the proto-oncogene is defective the protein can not be produced properly. Without the proper production of the protein cancers are more likely to develop. The survival rates for cancer depend upon what type of cancer...

Lung, Ovarian and Cervical cancers tend to have lower survival rates because by the time symptoms appear, the cancer is in a later stage. Other cancers that are caught in early stages such as stage one or stage two are usually treatable and the prognosis for survival can be rather good.
As it pertains to treatment there are several options that patients have including chemotherapy, radiation, changes in diet and more experimental treatments. The type of treatment the patient receives depends upon the type of cancer and the stage of the cancer. Some people do not receive any treatment at all for slow growing cancers; their doctors just monitor the growth of the cancer.

REFERECES

Campbell Reese, Simon. Essential Biology With Physiology.

Understanding Cancer Series. http://www.cancer.gov/cancertopics/understandingcancer/cancer/Slide1