Prostate cancer is the most common cancer among males and the fourth leading cause of cancer death in men. The prostate is a gland about the size of a walnut that is part of the male reproductive system. It is inside the pelvis at the base of the penis, just below the bladder and above the rectum. The prostate secretes the fluid that mixes with sperm to form semen. One in 11 white males and one in nine African-American males will develop prostate cancer in their lifetime. In addition to having a higher incidence, African-American men tend to develop prostate cancer at an earlier age. Men with a family history of prostate cancer and men over 60 have a greater risk of developing the disease. Another risk factor is a high-fat diet. Although prostate cancer often has no symptoms in its earliest stages, warning signs the cancer has advanced include difficulty or inability to urinate; frequent urination, especially at night; weak or interrupted urine flow; pain or burning upon urination or ejaculation; and blood or pus in the urine or semen. Persistent pain in the lower back, hips, and upper thighs can also suggest prostate cancer even when other symptoms are absent. If you have any of these symptoms, see a healthcare professional as soon as possible.