The cause of prostate cancer is unknown. It is known, however, that male hormones, especially testosterone, stimulate the growth of cancer cells in the prostate, along with normal prostate cells. We know that approximately 10% of prostate cancers are inherited. Men with a first-degree relative (father, brother) who have a prostate cancer diagnosed prior to age 65 have three times the risk of developing prostate cancer. The same risk is not present if one’s father or brother had a prostate malignancy detected after age 75.
There is a similar worldwide incidence of prostate cancer on autopsy study, yet the incidence of clinical cancer varies widely. Moreover, there is a three to sevenfold increased incidence of prostate cancer in first generation Chinese or Japanese Americans as compared to men in their homeland. This strongly suggests that environmental factors may play a role in cancer development, including diet, alcohol and tobacco consumption. Several epidemiological studies have demonstrated a link between diets rich in saturated fats (milk and meat) and higher prostate cancer risk.
African-American men have the highest incidence of prostate cancer in the world and, more importantly, a higher death rate. Initially, this was thought to be attributed to a reduced access to health care and screening programs; however recent studies in which physical examinations and screening were compulsory have verified the higher risk for prostate cancer and prostate cancer death in this population. The cause(s) are not known but may be related to diet and other factors.
| 5 year survival data (%) | ||
| Prostate Cancer Stage | Caucasian | African-American |
| Localized | 95 | 88 |
| Locally advanced | 87 | 69 |
| Metastatic | 30 | 23 |
| All stages | 89 | 73 |
Benign Prostatic Hypertrophy (BPH) does not cause prostate cancer. Beginning at age 30, under the influence of the male hormone testosterone, the middle portion (the transition zone) of the prostate begins to enlarge. As a man gets older, this enlargement leads to the commonly experienced symptoms of urinary frequency, urgency, slowing of the urine stream and having to get up at night to urinate. It should be noted, however, that BPH and these subsequent voiding symptoms can coexist with prostate cancer. Voiding difficulty in men with localized prostate cancer is attributed to coexisting BPH rather than early prostate cancer.