The prostate is a male sex gland responsible for producing fluid that forms semen. It is located below the bladder, in front of the rectum and surrounds the urethra. The prostate is divided into three zones enclosed by a capsule. The prostate capsule separates the prostate from the rest of the body.
The prostate gland typically enlarges as men grow older. This growth of the gland is called benign prostatic hypertrophy (BPH) and most often occurs in the transition zone of the prostate, which surrounds the urethra. Prostate growth in this area may block the bladder or urethra and prevent the flow of urine. Men may experience frequent or painful urination; blood in the urine or semen; and stiffness or pain in the lower back. These symptoms may be caused by BPH or they may be signs of cancer.
Prostate cancer occurs when the cells in the prostate gland grow out of control. When cells grow out of control, they initially spread within the prostate and then grow through the capsule that covers the prostate into neighboring organs, or break away and spread through the bloodstream and lymphatic system to other parts of the body. Prostate cancer can be relatively harmless or extremely aggressive. Some prostate cancers are slow growing, causing few clinical symptoms. In these cases, a patient will often die with prostate cancer rather than from prostate cancer. Aggressive cancers spread rapidly to the lymph nodes, other organs and especially, bone.
The suspicion of prostate cancer usually arises from an elevated prostate-specific antigen (PSA) blood level test and/or a digital rectal exam (DRE). PSA is a protein that is normally secreted and disposed of by the prostate gland. High PSA levels sometimes indicate the presence of cancer; however, more tests are needed to confirm this suspicion. During a DRE, a physician inserts a gloved finger into the rectum to assess the texture and size of the prostate.
If the results from a PSA blood test and/or a DRE suggest that prostate cancer may be present, this suspicion needs to be confirmed by a biopsy. Prostate cancer is diagnosed by performing one or more biopsies of the prostate gland. The biopsy will determine whether a patient has BPH, cancer or another medical problem. During a biopsy, a needle is used to remove several small pieces of prostate tissue through the rectum. These tissue samples are then examined under the microscope to determine whether cancer cells are present.
If cancer cells are present, the next step is to determine the stage or extent of spread of the cancer. Determining the extent of the stage of the cancer may require a number of procedures, including additional surgery (lymph node evaluation), blood tests, ultrasound, chest x-rays and occasionally, CT/MRI or bone scans. Cancer that is removed by surgical resection or needle biopsy will be classified according to the Gleason Grading System for prostate cancer. This grading system, on a scale of 2-10, helps physicians predict how rapidly the cancer is likely to spread. Higher Gleason scores are associated with more advanced and more rapidly growing cancers than lower scores.
All new treatment information concerning prostate cancer is categorized and discussed by stage. When patients have early stage cancer, the Gleason score and PSA blood level provide additional information that will help them make treatment decisions.
Prostate-specific antigen (PSA) blood test: PSA is a protein that is normally secreted and disposed of by the prostate gland. In patients with a known diagnosis of prostate cancer, the PSA level roughly reflects the total amount of cancer. The higher the PSA level, the more likely that the cancer is advanced.
Doctors will refer to the stage of prostate cancer by either a number or a letter. In order to learn more about the most recent information available concerning the treatment of prostate cancer, click on the appropriate stage
Stage I: The tumor (cancer) is not detectable with a physical examination.
T1a: The tumor is found when the prostate tissue is taken for some other reason. The tumor involves 5% or less of the prostate sample.
T1b: The tumor is found when the prostate tissue is taken for some other reason. The tumor involves more than 5% of the prostate sample.
T1c: The tumor detected by needle biopsy, or because the patient has a high blood level of PSA.
Stage II: The cancer is detectable with a physical examination, but is confined within the prostate.
T2a: The tumor involves half or less of a section (lobe) of the prostate.
T2b: The tumor involves half or more of a section (lobe) of the prostate, but the other section isn’t involved at all.
T2c: The tumor involves both sections (lobes) of the prostate.
Stage III: The cancer extends through the capsule of tissue that surrounds the prostate.
T3a: The tumor has extended outside of the prostate on one side.
T3b: The tumor has extended outside of the prostate on both sides.
T3c: The tumor has invaded one or both of the seminal vesicles, which are small bag-like organs near the bladder.
Stage IV: The cancer involves structures outside the oprostate other than the seminal vesicle.
T4: The tumor has invaded other nearby organs, including part of the bladder, the sphincter, or the rectum.
D1: The tumor has spread to pelvic lymph nodes or is obstructing the ureters (the tubes from the kidneys to the bladder), or both.
D2: Cancer spread (metastasis) to lymph nodes outside the pelvic area, bone involvement, or spread to other distant parts of the body.
Recurrent/Relapsed: The prostate cancer has been detected or has returned (recurred/relapsed) following an initial treatment with surgery, radiation, hormonal therapy, or chemotherapy.
D3: Distant cancer spread as in D2, and the cancer is resistant (does not respond) to hormonal therapy.