When evaluating the impact of a screening program, researchers and public health officials must weigh not only the benefits of the program, but also the potential harm that follows the introduction of the program. Unfortunately, little information is available from clinical trials that support the efficacy of intervention. Several publications have documented the complications associated with intervention, including the risk of incontinence bowel irritation and impotence. Decision analyses of screening have suggested that quality-adjusted survival may be compromised by screening, while decision-analytic models question the ability of screening and treatment to alter outcomes among men aged over 70, especially those with well- and moderately differentiated disease.

From a public health perspective, does screening cancer do more good than harm?

In assessing the value of testing for serum PSA, the impact on alternative health care services must also be considered. Screening for prostate cancer consumes health care resources that may be more appropriately deployed for other health care purposes, such as breast cancer screening, childhood immunizations or dietary counseling. Primary care physicians must deal with many preventive health care issues such as hypertension, high cholesterol or smoking cessation. Time devoted to prostate cancer screening comes at the expense of other significant health care problems, such as heart disease, diabetes and lung disease. At the national level, researchers have suggested that the introduction of routine prostate cancer screening within United States is likely to cost several billion dollars. This large investment may be worth-while, but at the present time this remains unproved.

Is the value of screening already proven?

Based upon the long natural history of prostate cancer and the relatively recent introduction of prostate cancer screening, definitive evidence concerning whether prostate cancer screening and treatment improve health will be unavailable until early in the next decade. Trends in prostate cancer mortality should become more definitive and results from ongoing clinical trials should become available. For now, the controversy surrounding prostate cancer screening revolves around an appropriate national policy regarding screening. Advocates cite the large number of men who die annually from prostate cancer as sufficient justification to initiate screening programs. They argue that lives can potentially be saved by near detection and treatment of this disease. Critics argue that the complication and cost associated with screening are not sufficient to justify wide programs. Until better data become available this debate cannot be resolved.

How should patients be counselled?

Since there is insufficient evidence either to support or to dismiss prostate cancer screening, physicians should neither encourage nor discourage PSA testing for the individual patient. Ideally, physicians should discuss the potential risks and benefits with each of their patients, but realistically few physicians have sufficient time. Many men come with preconceived ideas that have been formulated from incomplete or inaccurate information derived from acquaintances, advertisements and the media. Assessing patient preference and determining the likelihood that a patient will benefit from screening are also part of the physician’s responsibility. Screening a man with a life expectancy of less than 10 years is unlikely to benefit the patient and may result in a significant decrement in quality of life. From a public health perspective, mass screening for prostate cancer with public funds remains an uncertain investment. Mass screening may result in a significant decline in prostate cancer mortality rates, or it may have little impact on prostate cancer mortality. Until the value of prostate cancer screening is proved or disproved, pubic health officials and legislators face a difficult choice about whether to support screening effort. Unfortunately, the data that are currently available do not justify prostate cancer screening as a public health benefit.