The prostate is a gland in a man’s reproductive system. It makes and stores seminal fluid, a milky fluid that nourishes sperm. This fluid is released to form part of semen.
The prostate is about the size of a walnut. It is located below that bladder and in front of the rectum. It surrounds the upper part of the urethra, the tube that empties urine from the bladder. If the prostate grows too large, the flow of urine can be slowed or stopped.
To work properly, the prostate needs male hormones (androgens). Male hormones are responsible for male sex characteristics. The main male hormone is testosterone, which is made mainly by the testicles. Some male hormones are produced in small amounts by the adrenal glands.
Prostate cancer: Who’s at risk?
The causes of prostate cancer are not well understood. Doctors cannot explain why one man gets prostate cancer and another does not. Researchers are studying factors that may increase the risk of this disease. Studies have found that the following risk factors are associated with prostate cancer:
- Family history of prostate cancer
- Diet and dietary factors
Although a few studies suggested that having a vasectomy might increase a man’s risk for prostate cancer, most studies do not support this finding. Scientist has studied whether benign prostatic hyperplasia, obesity, lack of exercise, smoking, radiation exposure, or a sexually transmitted virus might increase the risk for prostate cancer. There is little evidence that these factors contribute to an increased risk.
Early prostate cancer often does not cause symptoms. But prostate cancer can cause any of these problems:
- A need to urinate frequently, especially at night;
- Difficulty starting urination or holding back urine;
- Inability to urinate;
- Weak or interrupted flow of urine;
- Painful or burning urination;
- Difficulty in having an erection;
- Painful ejaculation;
- Blood in urine or semen; or
- Frequent pain or stiffness in the lower back, hips, or upper thighs.
Any of these symptoms may be caused by cancer of by other, less serious health problems, such as BPH or an infection. A man who has symptoms like these should see a doctor or an urologist (a doctor who specializes in treating diseases of the genitourinary system).