Men should have their prostate gland checked regularly, regardless of whether they have symptoms, the American Cancer Society recommends.

Every year, men over 40 should have a rectal exam in which the physician places a gloved finger in the rectum to feel whether the prostate is enlarged or has hardened nodules. Half of the hardened nodules prove to be cancer.

Symptoms sometimes appear because the prostate surrounds the urethra, the tube that carries urine from the bladder and through the penis. As the prostate grows -- either from cancer or from benign prostate hypertropy, a noncancerous enlargement of the gland -- urine flow can become obstructed. It either becomes difficult to begin the urine flow or the stream will be weak or interrupted.

Because the growing prostate can press on the bladder, diminishing its capacity to hold urine, some men experience sudden urgency to urinate or must urinate frequently, sometimes interrupting sleep. Other symptoms can include blood in the urine, a painful burning sensation while urinating and back pain.

While many of these symptoms can be caused by other diseases, the cancer society suggests a physician be consulted when any of them occur. Prostate cancer is then confirmed by diagnostic tests, including ultrasound, biopsy and surgery.