The concept of screening patients for the early diagnosis of cancer in order to favorably impact on prognosis is not a novel idea. As early as in the 1950s, it was found that ovarian cancers could be diagnosed prior to becoming symptomatic by annual pelvic examination and that the incidence of rectal carcinoma decreased in patients receiving regular sigmoidoscopy, presumably due to early detection and removal of adenomas and polyps [1]. More recently, a large-scale study demonstrated a 30% decline in mortality from multiple cancers, including carcinoma of the prostate, and suggested that an inverse relationship exists between the frequency of check-ups and mortality rate [2], These studies, as well as a host of others have been criticized for failure to include properly selected control populations, inadequate sample size and followup procedures, poor documentation of survival statistics, contamination of the control population by screening modalities and numerous other methodological problems. Nevertheless, screening for breast cancer and cervical cancer is widely accepted and is considered useful in reducing mortality and improving the quality of life. Data support the reduction in mortality as a consequence of screening for cancers of the breast (mammogram), cervix (pap smears) and colon (sigmoidoscopy) [3-5]. Screening for other types of cancers, however, is more controversial [6-8].