"...it is apparent that dietary measures may significantly affect cancer incidence and mortality."
Prostate cancer is the most commonly diagnosed malignancy and the second leading cause of cancer death in men. Despite these facts, the American Cancer Society has recently provided encouraging news. Revised estimates indicate that approximately 184,500 men will be diagnosed with prostate cancer in 1998 and that 39,200 men will die from this disease. Both estimates for prostate cancer incidence and mortality are significantly lower than the estimates made one year ago. This means that for the first time, deaths due to prostate cancer are now declining in the United States. The reasons for this decline are unclear but may be associated with earlier detection and more effective treatments for this potentially fatal disease. Several risk factors have been identified. These include increasing age, African American race, and a positive family history of prostate cancer in a first degree relative. Other risk factors are less well established. However, a diet high in animal fat has been recently implicated. It is also well known that a high level of serum prostate specific antigen (PSA) is also implicated with increased cancer risk.
In addition to the exciting news of the decreased incidence and mortality of prostate cancer are the results of two studies which have addressed the issue of prostate cancer prevention using medication prevention. One of these studies has demonstrated a decrease in prostate cancer incidence and mortality, and the other study demonstrated a decreased incidence of prostate cancer.
A study performed in Finland and originally published in 1994 has been recently updated. In this study, patients were given vitamin E (alpha-tocopherol), 55 International Units (IU) a day. The study demonstrated the incidence of prostate cancer was reduced by 36 percent and most significantly and unprecedented was the finding that the mortality from prostate cancer was reduced by 41 percent in men receiving vitamin E supplementation compared to those men not receiving it. Confirmatory clinical trials need to be performed to further substantiate these findings. In the southeastern United States, a large study was performed to evaluate the effectiveness of selenium supplementation on the incidence of skin cancers. The patients in the study received 200 micrograms of selenium daily. While there was no effect on the incidence of recurrent skin cancers, there were statistically significant decreases in non-skin cancer risk, including a decrease in the incidence of prostate, lung, and colorectal cancers.
The findings were most impressive: there was a 63 percent reduction of prostate cancer in the group of patients receiving selenium. Again, further studies need to be performed to confirm the results. These two studies are highly encouraging, and while the medical establishment at this time cannot recommend medicationn for prevention of cancer, it is apparent that dietary measures may significantly affect cancer incidence and mortality. The important issue remains, early detection so that the condition can be discovered early at its most curable state. Yearly examination with PSA and prostate ultrasound testing have been highly effective in diagnosing these early curable stages of prostate cancer.
The American Cancer Society recommends that all men over the age of 40 should have a yearly rectal examination. Men over the age of 50, or those over 40 with a family history or of Black American ancestry, should have an annual PSA test. Prostate cancer is the second leading cause of cancer death for men living in the United States. Hopefully, with ongoing studies more risk factors can be identified, preventative measures can be identified, early detection will continue to be effective in diagnosing early curable cases, and ultimately the incidence and the mortality from this disease will continue to decline.