Stage IV prostate cancer means that the original cancer has spread to other locations within the body, states Texas Oncology. Stage IV prostate cancer is classified as D1 or D2 prostate cancer depending on where the cancer has spread within the body. D1 prostate cancer is localized, and has spread to adjacent organs or lymph nodes.
Texas Oncology states that D1 prostate cancer can include the bladder, kidneys and pelvic lymph nodes. The cancer may obstruct the ureters, the tubes that connect the kidneys to the bladder. D2 prostate cancer has spread beyond the adjacent organs, which may include the bones, spine, ribs and other internal organs. Stage IV prostate cancer also is called metastatic prostate cancer. It is difficult to cure, but treatment is still available. Patients with stage IV prostate cancer may live from six months to several years depending on the health of the patient. Stage IV cancer can be treated, but not cured, with hormone therapy, chemotherapy, immunotherapy and other strategies to improve the patient's quality of life.
According to the American Cancer Society, the five-year survival rate for D2 stage IV prostate cancer is 28 percent, while the five-year survival rate for localized D1 stage IV prostate cancer is nearly 100 percent.