Biological characterization of laryngeal squamous-cell carcinoma.

The traditional prognostic factors, including stage of disease and tumour grade, have shown a limited prognostic significance and an inability to predict clinical response to specific treatment in patients with laryngeal squamous-cell carcinoma. More recent data suggest that cell kinetics indices, DNA-ploidy, lysosomal cysteine proteinase expression and genetic changes of both tumour suppressor genes and protooncogenes may be considered as reliable and reproducible indicators of biological aggressiveness in these patients. Moreover, the frequency of different genetic alterations suggests that several pathways are involved in the genesis of these neoplasias and, in particular, it is very probable that p-53 expression and PCNA indices (increased in normal mucosa and preinvasive lesions) may constitute more important biomarkers for the early steps of laryngeal carcinogenesis.