Cancer hormone prostate treatment

Prostate cancer is second only to lung cancer as the leading cause of cancer deaths in American men. In 1997, approximately 209,900 new cases of prostate cancer were diagnosed, and more than 41,800 deaths were attributed to this malignancy.[1] At present, chemotherapy and immunotherapy cannot cure prostate cancer once it has spread beyond the gland. Therefore, curative treatment for localized tumors may be the best hope of lowering the mortality rate for prostate cancer.[1] According to this viewpoint, the primary focus of prostate cancer management should be the detection and aggressive treatment of tumors while they are still confined to the prostate.

The discovery of prostate-specific antigen (PSA) has made it possible to detect tumors before they become palpable on rectal examination. Improvements in radiotherapy and surgical techniques have decreased the complications of treatment and provided acceptable cure rates. However, the enthusiasm for prostate cancer screening must be tempered by the lack of evidence that its routine use can improve the quality and quantity of life for the overall population. Furthermore, a prostate cancer screening program is expensive, and the present treatments for this malignancy can be associated with significant side effects.

The controversial aspects of prostate cancer screening are reviewed in this article. An attempt is also made to identify the patient groups that definitely would benefit from prostate cancer screening. Current treatment approaches for tumors confined to the prostate are also reviewed.

Prostate Cancer Screening Controversy

The effectiveness of a cancer screening program depends on a number of factors. The malignancy must be detectable with minimal harm and cost, and early diagnosis must be able to improve the quantity and quality of the patient's life. An effective treatment for the cancer must be available, and this treatment should have few side effects. Finally, treatment of the asymptomatic patient must provide a better outcome than treatment after the disease has become clinically evident.

At this time, prostate cancer screening does not fulfill all of the requirements for an effective screening program. Some evidence shows that, compared with screening by rectal examination alone, routine screening of asymptomatic patients with PSA testing and digital rectal examinations detects a higher percentage of cancers that are localized to the prostate.[2] However, both the American Academy of Family Physicians[3] and the U.S. Preventive Services Task Force[4] recently recommended against the use of routine prostate cancer screening for two reasons: (1) early prostate cancer detection has no proven benefit and (2) the potential side effects of treatment may outweigh the benefits. In contrast, the American Cancer Society and the American Urological Association[5] recommend the use of a PSA-based screening program to detect prostate cancer in men 50 years of age and older.

The main problem with prostate cancer screening is that even though this malignancy is extremely common, it is the actual cause of death in only a small proportion of patients who have histologic evidence of prostate cancer. Although data from autopsies indicate that approximately 70 percent of 80-year-old men have prostate cancer,[6] this malignancy is the cause of death in only 3 percent of all men.[7] Prostate cancer is often an incidental finding in elderly patients. The tumor grows so slowly that no symptoms appear; in essence, patients often die of other causes before the cancer causes serious problems. Thus, prostate cancer screening programs may result in the detection and treatment of many asymptomatic cancers that will have no impact on length of life.

In the era of medical cost containment, the expense of a prostate cancer screening program must be considered, especially because other preventive health care measures, including smoking cessation programs, colon cancer screening, vaccination programs and prenatal care programs, may have greater impact on the overall health of the total population. These potentially more useful programs compete for funding with prostate cancer detection programs.

Although an individual PSA test is relatively inexpensive ($20 to $40), expenses multiply when a patient with an abnormal PSA test must be evaluated. Transrectal ultrasound examination costs approximately $100 per patient, and random biopsies cost another $150. Pathologic evaluation of the biopsy specimens costs approximately $300 per patient. When compounded by the fact that three patients without cancer must be evaluated for each cancer that is detected,[8] the estimated overall cost of initiating a nationwide prostate cancer screening and treatment program for all eligible men ranges from $8.5 to $25.7 billion per year.[9]

Prostate cancer screening does have a number of potential benefits. Evidence exists that screening programs based on PSA testing will detect only clinically significant malignancies (i.e., larger and more aggressive tumors that will cause significant symptoms or decrease the patient's life span if they are left untreated).[10] Furthermore, it is clear that every year more than 40,000 men die from prostate cancer. At present, early detection and treatment are the only effective measures for decreasing the mortality rate for this malignancy. Finally, some evidence shows that the aggressive diagnosis and treatment of prostate cancer is having an effect: 1997 was the first year in which the mortality and incidence rates for prostate cancer were expected to decrease.[11,12] It is too early to attribute these changes to prostate cancer screening programs initiated in the mid-1980s. However, screening programs that use PSA testing have been shown to reduce the number of patients who present with metastatic tumors or markedly elevated PSA levels.[2]

Indications for Prostate Cancer Evaluation

It is reasonable to search for prostate cancer in the male patient who is having difficulty voiding (slow stream, urgency) or hematuria, or who has signs and symptoms of metastatic cancer (bone spread resulting in an elevated alkaline phosphatase level and progressive back pain, sciatica or lower extremity neurologic impairment). Either curative treatments for cancers confined to the prostate (radical prostatectomy or radiotherapy) or palliative treatments for metastatic disease (orchiectomy to eliminate androgen stimulation to the tumor) are likely to decrease symptoms and improve quality of life.

Routine prostate cancer screening in asymptomatic patients is more controversial. The eventual decision to offer prostate cancer screening must be tempered by several factors: (1) prostate cancer has no cure once it has spread beyond the prostate, (2) prostate cancer treatment has potential complications, including impotence and incontinence, and (3) screening may identify a cancer that may never cause symptoms or decrease life expectancy.

The decision to offer prostate cancer screening must be made on an individual basis, depending on the patient's age, health status, family history, risk of prostate cancer and personal beliefs. The patient must be informed about the risks and potential benefits of screening. The patient also must be helped to realize that while prostate cancer can grow quickly, it generally grows quite slowly. In most men, a high-fat diet, smoking, lack of exercise and excessive alcohol intake can have a greater impact on life span than prostate cancer.

The risk of dying from prostate cancer is higher in certain patients, including all African-American men and men who have a first-degree relative with prostate cancer.[13] Since these men may be genetically predisposed to the development of prostate cancer, the American Urological Associations recommends that they be evaluated with annual PSA testing and rectal examinations, beginning at 40 years of age.

For all other men, prostate cancer screening should be performed at the age of 50 years in those who wish to undergo evaluation. Annual examinations can then be considered. Changes in the rectal examination or a rise in the PSA level of greater than 0.7 ng per mL per year are suggestive of cancer.

Prostate cancer screening probably should not be done once patients are over the age of 70 or if they develop a significant underlying medical illness or other incurable malignancy that will decrease their life expectancy to less than 10 years.

Approach to Prostate Cancer Screening