Editorial comment

      Bladder cancer is a common malignancy worldwide that causes substantial cancer-related morbidity and mortality. As superficial bladder cancer is not a curable disease, patients are facing a need for lifetime follow-up. Entering into the new millennium, we still cannot offer our patients with bladder cancer any new changes from our traditional invasive follow-up regimen. Cystoscopy and imaging studies are invasive, inconvenient, and carry significant morbidity. The frequently repeated tests also pose a great economic burden on health care systems. We have not yet found a specific and sensitive noninvasive tool to detect primary and recurrent bladder cancer. Analysis of cancer markers found in voided urine samples is the simplest, noninvasive, and most convenient method to detect bladder cancer. Before a new marker—such as described in this report—becomes a part of routine clinical practice, careful evaluation of the sensitivity, specificity, and predictive value of the test must be made in a large-scale study. It is important to understand that even a test that has more than 90% sensitivity and specificity can still result in a high proportion of inaccurate results when the prevalence of the disease is low in the population being studied.
      Most of the studies done on bladder cancer markers included a relatively small number of patients, unproportional to the epidemiology and extent of the bladder cancer population worldwide. The majority of the markers are experimental only, demanding the use of specific laboratories and equipment, and hence unsuitable for routine clinical use. Other commercially available markers cannot yet replace cystoscopy.
      There is an urgent need to find a highly specific and sensitive bladder cancer marker to improve detection accuracy, reduce patient morbidity and inconvenience, and decrease the follow-up financial burden. Only a prospective multicenter study with a large number of patients will enable us to establish a true marker; thereafter, it should be available in any hospital with a cost lower than urine cytology. Such marker does not yet exist.