Prostate Cancer

Introduction

The prostate is a walnut-sized gland in men that lies just below the bladder, surrounding the urethra. The function of the prostate is to enhance the movement of sperm cells by secreting a thin, lubricating fluid into the urethra.

Prostate cancer is the most common form of cancer, excluding skin cancer, in men in the United States. It is primarily diagnosed in men over 65, although it may begin much earlier. Some cancers of the prostate are very slow growing, while others behave aggressively. Prostate cancer often metastasizes to other tissue, including the brain, lungs, lymph nodes, and bones. Early detection is critical in order to increase the chances for survival. The cancer can be felt upon digital rectal examination (DRE). These examinations are recommended routinely for all men over the age of 50 and high-risk men should commence at age 40.

Little is known about the causes of prostate cancer. Risk factors for prostate cancer include family history and black race. While most prostate cancers are found in the peripheral zone, they may occur anywhere in the prostate. Most pathologists use the Gleason grading system to assess the tumor progression. A score from 2 to 4 indicates a well-differentiated cancer; 5 to 6 correlates with a moderately differentiated cancer; and 7 to 10 indicates a poorly differentiated cancer. The poorer the differentiation of the cancer cells (the higher the score), the worse the prognosis. Well-differentiated tumors grow slowly, whereas poorly differentiated tumors grow rapidly and are associated with a poor prognosis.

Statistic

Cancer Research UK, 2006.

  • Worldwide, more than 670,000 men are diagnosed with prostate cancer every year, accounting for one in nine of all new cancers in males.

  • It is the second most common cancer in men after lung cancer.

Second Report of National Cancer Registry in Malaysia, 2003.

  • In 2003, there were 602 cases reported (6.4%) making prostate cancer the 6th most common cancer among males in Malaysia.

  • The age specific incidence rate rises sharply after the age of 60.

  • The overall age standardized incidence was 10.3 per 100,000 population.

National Vital Statistics Reports, Vol. 48, No. 11.

    The annual number of deaths from Prostate Cancer are 32,203 (1998).

Vital and Health Statistics Series 10, No. 200.

    Cases of Prostate Disease Reported Annually: 2.8 million (1996).

Vital and Health Statistics Series 13, No. 143.

    Number of Ambulatory Care Visits for Prostate Cancer: 2.5 million (1997).

National Cancer Institute, National Institutes of Health (NIH), Department of Health and Human Services(HHS) 1998.

    The mortality rate of Prostate Cancer(1995) is 34,475 men die of it each year.

Signs and Symptoms

[span class=alert]The following list does not insure the presence of this health condition. Please see the text and your healthcare professional for more information.[/span]

In cases of sudden prostate swelling there will be a sudden onset of fever, chills, lower back pain, and pain in the groin area. These symptoms may indicate the development of an infection as in acute bacterial prostatitis. Increased number of trips to the restroom for urination and burning with urination are likely experienced. These trips to the restroom for urination are hurried and necessary. The man will also note an increase in the number of trips to the restroom at night.

With long-term prostate swelling, the type generally found in BPH, chronic prostatitis or prostate cancer, there would be an increased number of hurried and necessary trips to the restroom for urination. Difficulty in starting the urine stream may also be experienced. The individual may also note puss or oozing from the penis.

Prostate cancer, like BPH, may initially have no symptoms. Eventually there will be an increased number of trips to the restroom for urination, which are hurried and necessary. An increase in the number of trips to the restroom at night, difficulty in starting the urine stream and a decrease in the force of the urine stream will be experienced. Cancer differs from BPH in that the individual will experience fatigue, nausea, weakness, back pain, hip pain, and swollen lymph nodes. There will likely be discomfort in the area between the scrotum and the anus and eventual weight loss. Blood may be present in the urine.

General

  • Initially, no symptoms may be present
  • Increased number of trips to the restroom for urination
  • Trips to the restroom for urination are hurried and necessary
  • Increase in the number of trips to the restroom at night
  • Increased difficulty in starting the urine stream
  • Decrease in the force of the urine stream
  • Fatigue
  • Nausea
  • Weakness
  • Back pain
  • Swollen lymph nodes
  • Discomfort in the area between the scrotum and the anus
  • Hip pain
  • Weight loss
  • Blood may be present in the urine

Treatment Options

Conventional

Prostate cancer screening is used to detect the tumor while it is still located in the prostate alone and is most easily and successfully treated. Biopsy of the prostate is essential for establishing the diagnosis and is indicated when a problem is detected by DRE or elevated Prostate Specific Antigen (PSA), a lab marker for the detection of prostate cancer.

Treatment of prostate cancer is determined by the stage of the disease. If the cancer is limited to the prostate, radical prostatectomy, or removal of the prostate is usually performed, with or without radiation therapy. A recent study found, however, that men who had their prostates removed after diagnosis did not survive considerably longer than those whose cancers were monitored without surgery. (1) , (2) For later stages of cancer, treatment usually consists of general care for the patient. Chemotherapy is reserved for hormone-unresponsive disease.

Nutritional Suplementation


Lycopene

Lycopene is a dietary component that seems to provide specific protection against prostate cancer. Results from the Health Professionals Follow-Up Study reported a lower prostate cancer risk among men who consumed larger quantities of tomatoes and related lycopene-containing food products. (3) In another study, lower levels of lycopene were observed in men with prostate cancer compared to controls. (4)

Tomatoes are the primary dietary source of lycopene. Lycopene concentration is highest in cooked tomato products. It is interesting to note that the highest concentrations of lycopene occur in the testes, adrenals, and prostate gland. (5) It is estimated that a minimum 4-6mg daily intake of lycopene is needed for prostate protection.


Selenium

The following study suggests that selenium supplementation may provide significant protection against prostate cancer. Nine hundred and seventy-eight men received either a daily supplement of 200mcg of selenium or a placebo. These men were treated for an average of 4.5 years and then followed for an additional 6.5 years. Men that initially had normal PSA levels revealed that selenium supplementation was responsible for a 63% reduction in the incidence of prostate cancer. Four men were diagnosed in the selenium-treated group, compared to 16 cases of prostate cancer in the placebo group. Additionally, compared to placebo controls, the individuals taking selenium also had significant reductions in colorectal cancer and lung cancer. (6)


Vitamin E

The results of a study that evaluated the incidence of prostate cancer and deaths among male smokers who took vitamin E indicated that men taking 50mg of vitamin E daily had a 32% lower incidence of prostate cancer, and a 41% reduction in deaths from prostate cancer. (7)


Zinc

In order to insure the general health and well being of the prostate gland, zinc supplementation may be warranted. The prostate gland stores zinc and the concentration of zinc in the prostate gland is much higher than in other tissues in the human body. (8) Adequate zinc levels help to prevent enlargement of the prostate gland. This is because zinc influences the activity of the 5 alpha-reductase enzyme, affecting the rate on conversion of testosterone to dihydrotestosterone (DHT). (9) Zinc may not only prevent prostate enlargement, animal studies report it may also help to shrink a gland that is already swollen. (10) Men taking over 100mg of supplemental zinc daily may have a higher risk of advanced prostate cancer than nonusers. (11)


Vitamin B6

Taking zinc alone isn’t enough to insure prostate health. Vitamin B6 influences zinc absorption. Apparently vitamin B6 helps to convert zinc to a form that is more absorbable by the tissues in the prostate. (12) Studies indicate that vitamin B6 is deficient in the diet of many Americans, a factor that may contribute to low zinc status and increased prostate problems. For example, data from the Second National Health and Nutrition Examination Survey (NHANES II) reported that 71% of males consumed less than the RDA for vitamin B6 on a daily basis. (13)

Herbal Suplementation

A study recently published assessed dietary and environmental risks associated with prostate cancer. Through the World Health Organization, prostate cancer mortality rates were gathered for 32 countries. In addition, the researchers obtained dietary information from the Food and Agricultural Organization. After analyzing all the data, the results showed that one of the major contribution factors to prostate cancer risk was a high intake of animal products. Also found to contribute to this risk were alcohol and nonfat milk. A higher intake of onions was found to reduce the risk, followed by other vegetable products. The authors concluded that the allium (found in onions) food family was associated with a reduced risk of prostate cancer. (14)

Diet & Lifestyle

Dietary fat: There are many studies that discuss how various factors related to diet and nutrition influence cancer. Although only a small amount of this research relates directly to the prevention or treatment of prostate cancer, the following reviews have been reported.

Most studies that have evaluated the relationship between dietary fat and prostate cancer report that diets high in total fat are associated with an increased rate of prostate cancer. (15) , (16) Increased meat and dairy consumption is likely related to an increased risk of metastatic prostate cancer or prostate cancer that has spread throughout the body, but increased risk did not apply to all cases of prostate cancer evaluated. (17)

References

  1. View Abstract: Matos-Ferreira A. New review of radical prostatectomy. Actas Urol Esp. Oct1997:817-21.
  2. View Abstract: Fleming C, Wasson JH, Albertsen PC, Barry MJ, Wennberg JE. A decision analysis of alternative treatment strategies for clinically localized prostate cancer. JAMA. May1993;269:2650-8.
  3. View Abstract: Clinton SK, et al. Cis-trans lycopene isomers, carotenoids, and retinol in the human prostate. Cancer Epidemiol Biomarkers Prev 1996 Oct;5(10):823-833.
  4. View Abstract: Rao AV, et al. Serum and tissue lycopene and biomarkers of oxidation in prostate cancer patients: a case-control study. Nutr Cancer. 1999;33(2):159-64.
  5. View Abstract: Gerster H. The potential role of lycopene for human health. J Am Coll Nutr. Apr1997;16(2):109-126.
  6. View Abstract: Clark LC, et al. Decreased incidence of prostate cancer with selenium supplementation: results of a double-blind cancer prevention trial. Br J Urol. May1998;81(5):730-4.
  7. View Abstract: Heinonen, OP. Prostate cancer and supplementation with alpha tocopherol and beta-carotene: Incidence and mortality in a controlled trial. J Natl Cancer Inst. Mar1998;90(6):440-446.
  8. View Abstract: Pavon Maganto E. Zinc in prostatic physiopathology. I. Role of zinc in the physiology and biochemistry of the prostatic gland. Arch Esp Urol. Mar1979;32(2):143-52.
  9. View Abstract: Leake A, et al. The effect of zinc on the 5 alpha-reduction of testosterone by the hyperplastic human prostate gland. J Steroid Biochem. Feb1984;2092:651-655.
  10. View Abstract: Fahim MS, et al. Zinc arginine, a 5 alpha-reductase inhibitor, reduces rat ventral prostate weight and DNA without affecting testicular function. Andrologia. Nov1993;25(6):369-375.
  11. View Abstract: Leitzmann MF, Stampfer MJ, Wu K, Colditz GA, Willett WC, Giovannucci EL. Zinc supplement use and risk of prostate cancer. J Natl Cancer Inst. Jul2003;95(13):1004-7.
  12. View Abstract: Evans GW, Johnson EC. Effect of iron, vitamin B-6 and picolinic acid on zinc absorption in the rat. Journal of Nutrition. Jan1981;111(1):68-75.
  13. View Abstract: Kant AK, Blcok G. Dietary vitamin B-6 intake and food sources in the US population: NHANES II, 1976-1980. Am J Clin Nutr. Oct1990;52(4):707-16.
  14. View Abstract: Grant WB. A Multicountry Ecologic Study of Risk and Risk Reduction Factors for Prostate Cancer Mortality. Europ Urol. doi:10.1016/j.eururo.2003.08.018.
  15. Rose DP, Connolly JM. Dietary fat, fatty acids and prostate cancer. Lipids. 1982;27:798-803.
  16. View Abstract: Hursting SD, et al. Types of dietary fat and the incidence of cancer at 5 sites. Prev Med. 1990;19:242-253.
  17. View Abstract: Michaud DS, Augustsson K, Rimm EB, Stampfer MJ, Willet WC, Giovannucci E. A prospective study on intake of animal products and risk of prostate cancer. Cancer Causes Control. Aug 2001;12(6):557-67.