Carcinoma of the Prostate - Incidence & Epidemiology
Prostate cancer is the most common cancer diagnosed and is the second leading cause of cancer death in American men. Of all cancers, the prevalence of CaP increases the most rapidly with age. However, unlike most cancers, which have a peak age of incidence, the incidence of CaP continues to increase with advancing age. The lifetime risk of a 50-year-old man for latent CaP (detected as an incidental finding at autopsy, not related to the cause of death) is 40%; for clinically apparent CaP, 9.5%; and for death from CaP, 2.9%. Thus, many prostate cancers are indolent and inconsequential to the patient while others are virulent, and if detected too late or left untreated, they result in a patient’s death. This broad spectrum of biological activity can make decision making for individual patients difficult.

Several risk factors for prostate cancer have been identified. As discussed above, increasing age heightens the risk for CaP. Which of the factors associated with the aging process are responsible for this observation is unknown. The probability of CaP developing in a man under the age of 40 is 1 in 10,000; for men 40-59 it is 1 in 103, and for men 60-79 it is 1 in 8. African Americans are at a higher risk for CaP than whites. In addition, African American men tend to present at a later stage of disease than whites. Controversial data have been reported suggesting that mortality from this disease may also be higher for African Americans. A positive family history of CaP also increases the relative risk for CaP. The age of disease onset in the family member with the diagnosis of CaP affects a patient’s relative risk. If the age of onset is 70, the relative risk is increased 4-fold; if the age of onset is 60, the relative risk is increased 5-fold; and if the age of onset is 50, the relative risk is increased 7-fold. High dietary fat intake increases the relative risk for CaP by almost a factor of 2. Another exposure that may increase the risk for CaP involves cadmium, which is found in cigarette smoke, alkaline batteries, and in the welding industry. Previous vasectomy has been suggested as a factor that heightens the risk for CaP, but these data are controversial.