Intermediate biomarkers in the colorectal tumor progression.

Intermediate biomarkers are biological alterations in tissue which signal a stage of carcinogenesis between initiation and the development of a malignant tumor. Proliferation biomarkers are those that most satisfy the requisites for premorphological intermediate markers in the colorectal tumor progression. Cell proliferation changes in histologically normal intestinal mucosa are early events directly and closely associated with the morphogenesis of colorectal neoplasia. The transition from the morphological stage and the latter's further progression can be reliably monitored through the use of differentiation and genomic markers. In particular the incidence and the degree of DNA aneuploidy are indicators of the risk of malignant transformation in colorectal adenomas. New "regression-related" biomarkers should be investigated for the planning of measures designed to bring about the regression of premalignant lesions.