According to the National Cancer Institute's Surveillance, Epidemiology and End Results (NCI's SEER) Cancer Statistics Review, the prostate cancer five-year survival rate is 100%. This five-year survival rate is high for two main reasons. First, many prostate cancers are slow enough in their growth rate that even if they remained untreated, most men would be able to live with their disease for more than five years before the cancer metastasized (spread to other sites) and eventually killed them. Second, about 80% of prostate cancers are detected quite early, when the disease is still localized to the prostate. This group of patients has a high cure rate long term with any of the currently available standard treatments. On the other hand, for patients who are diagnosed when the tumor has already spread to other sites, the five-year survival rate is 31%, according to NCI's SEER statistics.