Classification of head and neck tumors has evolved in recent decades including a widespread application of molecular testing in tumors of the salivary glands, sinonasal tract, oropharynx, nasopharynx, and soft tissue. Availability of new molecular techniques allowed for the definition of multiple novel tumor types unique to head and neck sites. Moreover, the expanding spectrum of immunohistochemical markers facilitates a rapid identification of diagnostic molecular abnormalities. As such, it is currently possible for head and neck pathologists to benefit from a molecularly defined classifications, while making diagnoses that are still based largely on histopathology and immunohistochemistry. This review highlights some principal molecular alterations in head and neck neoplasms presently available to assist pathologists in the practice of diagnosis, prognostication and prediction of response to treatment.

Bioptic Laboratory Ltd Pilsen Czech Republic

Institute of Biomedicine Pathology University of Turku and Department of Pathology Turku University Hospital Turku Finland

Molecular and Genetic Laboratory Bioptic Laboratory Ltd Pilsen Czech Republic

Sikl's Department of Pathology Faculty of Medicine in Pilsen Charles University E Benese 13 305 99 Pilsen Czech Republic

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