After a cancer diagnosis, one of the most common questions people have is about the severity of the disease, which is determined by if and how far it has spread. This is called staging, and there are five stages of prostate cancer. Ranging from I to IV, prostate cancer stages are an indicator of not only how far the cancer has spread, but also of the likelihood of long-term survival. As higher cancer stages are reached, the chances of an optimum outcome decrease. This is due to multiple areas being affected by the cancer as well as increased odds that the disease eventually relapses after successful treatment.

Stage I prostate cancer

Though not widely utilized as a stage for prostate cancer, stage 0 would indicate that cancer cells are present but only in the cells in which they originated and no tumor has yet developed. This would be an ideal diagnosis, but is not common. Following this would be stage I prostate cancer. For this stage, the cancer is still within the prostate gland and cannot be detected by digital rectal exams or ultrasounds. Instead, it is often discovered accidentally during surgery for other benign conditions of the prostate. Symptoms generally do not appear at this stage.

Stage II prostate cancer

Stage II prostate cancer means the disease remains within the prostate gland. However, at this stage it is usually detectable by digital rectal exams and other screening methods. If prostate-specific antigen (PSA) levels are discovered to be high on a blood test, needle biopsies may be able to find the cancer even if it can’t be found by other techniques. According to the National Cancer Institute, the Gleason score for this stage can range from the lowest score, 2, to the highest score, 10.

Stage III prostate cancer

If the prostate cancer has spread to the seminal vesicles or other nearby tissues, the disease can be staged at III. The tumor from this stage of prostate cancer can be easily found during a digital rectum exam or by tests such as MRIs. Though spreading has occurred at this stage of prostate cancer, the lymph nodes remain unaffected and spreading to distant organs has yet to happen.

Stage IV prostate cancer

Once stage IV prostate cancer is diagnosed, it means the cancer has spread to the lymph nodes or to distant areas of the body. This stage of cancer offers the worst prognosis, generally. The original tumor has progressed and grown significantly, and may even have reached the bladder or pelvic wall. Metastasis to the bones is common for prostate cancer at this stage. Treatments will usually be recommended together for counteracting cancer that has progressed this far. According to the American Cancer Society, 5-year relative survival rate for men with prostate cancer that has spread distantly is approximately 31 percent.