The prognosis for prostate cancer depends on how far the cancer has spread once the doctor detects the disease, according to WebMD. Doctors use one of four stages to describe how advanced prostate cancer has become in a patient. Stage I has the best prognosis, and Stage IV has the worst. Better prognoses depend on the location of prostate cancer.
WebMD explains that during Stage I prostate cancer, the tumor is so small it cannot be seen on imaging scans or felt during an exam. The cancer is localized to the prostate only. During Stage II, the tumor is larger but remains in the prostate. The local stage of prostate cancer has a nearly 100 percent chance of survival for the next five years, according to the American Cancer Society as of September 2014. Four out of five prostate cancers are detected during the local stage of the disease, or during Stage I and II.
Stage III prostate cancer indicates the disease has spread outside the organ but only into surrounding tissue. Also called the regional stage, the ACS explains the five-year survival rate is still nearly 100 percent. Stage IV occurs when prostate cancer has spread to distant organs, bones and lymph nodes. The five-year survival rate is 28 percent for Stage IV patients, as of September 2014.