Objective biologic parameters and their clinical relevance in assessing salivary gland neoplasms

This review summarizes research advances of cytometric, proliferation, cyto genetic, and molecular "objective" measurable parameters, as additional aid s to prognostic information of salivary gland tumors provided by classical clinicopathologic indicators. Flow cytometric DNA ploidy and S-phase fracti on seem to be of value as predictors of tumor behavior, aneuploidy, and hig h S-phase identifying an unfavorable clinical evolution of salivary gland n eoplasms. Cell proliferation markers assessed by immunohistochemistry (e.g. , PCNA, Ki-67) also appear to have predictive significance, but some confli cting results, in part related to technical procedures, limit their routine clinical application. Silver-stained methods (AgNORs) show a scarce value in estimating prognosis of salivary gland malignancies, p53 and c-erbB-2 as well as karyotyping, are of disputable benefit for clinical use, but the b iologic information they provide give a better understanding on the molecul ar mechanisms involved in the development and progression of tumors. Furthe r studies, with large databases, long follow-up information, uniformized hi stologic classification, and standardized methodologies, are needed to esta blish how these "objective" parameters would be of Truly beneficial for the treatment of patients with salivary gland tumors.