Prostate Cancer: Risk Factors, Detection, and Treatment

Cancer is the second largest cause of death in the United States today, claiming approximately 565,000 lives of the approximately 1.4 million people diagnosed with it each year (Insel and Roth 480, 482). While there is no vaccine or drug to reduce someone's chances of getting cancer, there are certain factors that one can educate himself/herself on in an attempt to minimize risk.

Genetic, environment, and lifestyle factors all play a major role in the occurrence of cancer in general. Uncontrollable factors are genetic predisposition, gender differences, and the environment in which one lives. Nearly five percent of all cancer deaths have been linked to family history of cancer, and roughly two percent are linked to environmental pollution (Insel and Roth 480). Men are more likely to acquire and die from cancer than women, which is reflected in the fact that in the U.S. nearly half of men and more than one third of women will be diagnosed with cancer in their lifetime (Insel and Roth 483). However, not all risk factors are uncontrollable. Lifestyle factors play a major role in one's likelihood of being diagnosed with cancer. Tobacco use, obesity, poor diet, sedentary lifestyle, alcohol use, ultraviolet radiation, and occupational factors greatly contribute to someone's risk. Combined, these are linked to nearly seventy-five percent of all deaths resulting from cancer (Insel and Roth 480).

The leading cancer in men is prostate cancer, with 234,500 new cases a year - nearly three times more than any other cancer in men (Insel and Roth 482). It is also responsible for nearly thirty thousand deaths each year in the U.S. alone (Karan, Lubaroff, and Thrasher 230).

Ethnicity, family history, age, lifestyle, and diet are the greatest risk factors for prostate cancer. Age in particular plays a large role in its incidence. According to Insel and Roth, "Age is the strongest predictor of the risk, with about 75% of cases of prostate cancer diagnosed in men over age 65" (488). Ethnicity also plays a large role, as risks for prostate cancer vary greatly among different ethnic groups. African American men have the highest incidence of prostate cancer, and are more than fifty times more likely to be diagnosed with prostate cancer than Chinese men (Bai 60). This is attributed somewhat to different lifestyle or environmental factors among different cultures. For example, Karan, Lubaroff, and Thrasher tell us in their article, "Prostate Cancer: Genes, Environment, Immunity and the Use of Immunotherapy" that, "Migrants to the United States, particularly of Asian origin, are at higher risk to develop prostate cancer compared to men who remain in Asia" (232). Additionally, family history and genetics have been estimated to account for forty percent of prostate cancer (Wolk 277). Other reasons for the difference among ethnic groups are still unknown.

Lifestyle may also play a role in the incidence of prostate cancer, as it is speculated, but not yet proven, that a high level of physical activity may reduce the risk of prostate cancer (Wolk 277). Diet is proven to play a major role its incidence, as high consumption of meat and dairy products has been shown to contribute to a higher incidence. Tomato products and fatty fish have been attributed to a reduced risk (Wolk 277). Wolk also tells us in her article, "Diet, Lifestyle and Risk of Prostate Cancer," that, "Increased intake of vitamin E and selenium (from supplements) has been shown in intervention studies to decrease the risk" (277). Altering just a couple dietary factors is one of the easiest ways to reduce one's risk of developing prostate cancer.

Early detection of prostate cancer may be difficult, as it usually has no symptoms, but warning signs can include "changes in urinary frequency, weak or interrupted urine flow, painful urination, and blood in the urine" (Insel and Roth 488). Tests for prostate cancer include the prostate-specific antigen (PSA) blood test, digital rectum exam, ultrasound, and needle biopsy. It is recommended that the PSA test be done annually for men age fifty or above with average risk, and for men age forty-five or above with high risk (Insel and Roth 488). However, the PSA test has its limitations, as it has been shown to give false positives in some cases. In a digital rectum exam, the doctor is feeling to make sure the prostate gland is not enlarged and does not have any lumps, which may indicate cancer. An increasingly used backup to digital rectum exams is the ultrasound, which is able to determine the size, shape, and properties of lumps, and may also find lumps too small to be detected by the digital prostate exam (Insel and Roth 488). If any lumps are found, a needle biopsy may be done to remove some of the lump for malignancy tests.

Various treatments for prostate cancer exist, but the most common treatment for those with organ-confined prostate cancer is radical prostatectomy (RPX), where the prostate is surgically removed (Fiadjoe 243). While it has the highest cure rate of all treatments, at least thirty to fifty percent of patients have recurring prostate cancer at some point (Pins 243). The primary alternative to RPX involves a less-invasive process, where radioactive seeds are surgically implanted. In this procedure, the tumor is destroyed from the radiation of these seeds (while little surrounding tissue is touched), but a lot of the normal prostate tissue is destroyed with the tumor (Insel and Roth 488). Other less common and less effective treatments include "external radiation, hormones that shrink tumors, cryotherapy, and anti-cancer drugs" (Insel and Roth 488). Treatments for prostate cancer are very effective, and the five-year survival rate is nearly one hundred percent (Insel and Roth 488).

Prostate cancer treatment has been shown to be effective, having high survival rates that are nearing one hundred percent. Still, as with most cancers, research is being conducted in an attempt to find possible future treatments to overcome the limitations of current procedures. The most promising innovations to date are gene therapy, gene chip technology, and proteomics (Schalken and Watson S8).

Prostate cancer is a major risk for men, but through taking the necessary precautions, treatments, and/or procedures, the chances for death are minimal. Awareness of prostate cancer is very important, as a more informed, more proactive society of men would greatly reduce not only the incidence of prostate cancer, but the number of deaths resulting from it as well. Through continuing research, the future of prostate cancer prevention and treatment is looking better than ever.

Works Cited

1. Bai, Y., et al. "Risk of Prostate Cancer and Family History of Cancer: A Population-Based Study in China." Prostate Cancer and Prostatic Diseases. 8.1 (March 1, 2005): 60-65. EBSCOhost. Georgia Tech Library. Atlanta, 27 Oct. 2008.

2. Insel, Paul M., and Walton T. Roth. Core Concepts in Health: Tenth Edition Update. United States of America: The McGraw-Hill Companies, Inc., 2008.

3. Karan, D., D. Lubaroff, and J. B. Thrasher. "Prostate Cancer: Genes, Environment, Immunity and the use of Immunotherapy." Prostate Cancer and Prostatic Diseases. 11.3 (February 19, 2008): 230-236. EBSCOhost. Georgia Tech Library. Atlanta, 27 Oct. 2008.

4. Pins, M. R., et al. "Clusterin as a Possible Predictor for Biochemical Recurrence of Prostate Cancer Following Radical Prostatectomy with Intermediate Gleason Scores: A Preliminary Report." Prostate Cancer and Prostatic Diseases. 7.3 (September 1, 2004): 243-248. EBSCOhost. Georgia Tech Library. Atlanta, 27 Oct. 2008.

5. Watson, R. W. G, and J. A. Schalken. "Future Opportunities For the Diagnosis and treatment of Prostate Cancer." Prostate Cancer and Prostatic Diseases. 7.Supplement 1 (September 1, 2004): S8-S13. EBSCOhost. Georgia Tech Library. Atlanta, 27 Oct. 2008.

6. Wolk, Alicja, et al. "Diet, Lifestyle and Risk of Prostate Cancer." Acta Oncologica. 44.3 (May 2005): 277-281. InformaWorld. Georgia Tech Library. Atlanta, 27 Oct. 2008.