The urethra is a tube like structure that brings urine from the urinary bladder towards the penis for excretion. Urethra lies on the pelvic floor, and the prostate glands are present in the pelvis, too surrounding the urethra. The development of cancer in the prostate glands causes impairment in the function of urethra. The inflammation in the prostate gland irritates the wall of the bladder by pressing against the urethra. The inflamed prostate gland blocks the flow of urine, and the constant strain of pressing from the prostate glands causes contraction of the bladder. When the bladder begins to contract to have small amounts of urine in it, there is more frequent urination.