The aim of this article is to review recent developments in the biological understanding of head and neck squamous cell carcinomas.

We describe the markers according to their function and their prognostic or predictive roles. Some associations can be found between molecular markers and invasiveness, aggressiveness, degree of differentiation, and tumor stage, but only a few clinical studies have shown an impact on prognosis. In addition, despite an increasing number of articles relating to this topic, the small number of patients included in the studies reported reduces the clinical implications of these results. Few studies applied a more comprehensive molecular analysis approach, such as DNA microarrays or differential expression profiling by polymerase chain reaction, to identify a combination of markers that could be more informative than a single molecular marker.

Some progress has been made with respect to molecular markers and head and neck cancers. Translational and prospective, hypothesis‐driven research must proceed with sufficient rigor to facilitate the clinical applicability of such results. © 2005 Wiley Periodicals, Inc. Head Neck 27: XXX–XXX, 2005