Head and neck cancers are a diverse group of diseases (such as oral cavity, oro/hypopharynx and larynx) with a worldwide annual incidence of more than 500,000 pa­tients. Unfortunately, despite improvements in both mod­ern therapeutic strategies and surgical management, a long-term survival rate is among the lowest for the major cancers. The tumors are characterized by local tumor ag­gressiveness, high rate of early recurrence and develop­ment of second primary carcinomas. These facts have encouraged the researchers to analyze the occurring ge­netic changes which probably may serve as prognostic indicators of patient survival or markers to select the pa­tient treatment.

This article gives basic information about the genetic changes that play a role in the development of head and neck squamous cell carcinoma (HNSCC), the methods that have been applied for the detection of these changes and their impact on patient outcome. The development of HNSCC is a consequence of malfunction of different oncogenes and tumor suppressor genes. These genetic changes occur in the mucosa of the upper aerodigestive tract and their accumulation is specific; it differs, depend­ing on the location of tumor initiation. Analysis of the expression of different proteins (e.g., cyclin D1, EGFR) in the three main anatomical regions, oral cavity, pharynx and larynx, showed different expression of products: high expression of cyclin D1 in the pharynx and low expression of EGFR in the larynx, compared to the other regions. This reveals the different biology of the origin of head and neck tumors and what is more, these genetic changes could be of prognostic and clinical importance [1].