Prostatic cancer: future prospects for diagnosis and screening

There are still no absolute tumour markers for cancers in most (if not all) tissues. Those markers that are available, other than those that physically detect a tumour, depend on organ-associated rather than tumour-specific proteins. Consequently, the likelihood of false positive or negative results is high. The ideal marker(s) should detect the presence of a tumour, its malignant potential, its stage in the progression pathway and the extent of spread. An added bonus would be for the marker to be organ-specific. Unfortunately, this paragon does not exist, but there are now experimental systems which can be exploited. Although all our requirements are not likely to be realized in the near future, some are within sight.