The salivary gland section in the 5th edition of the World Health Organization Classification of Head and Neck Tumours includes a description of several new entities. In addition, numerous tumor variants were described and new concepts proposed, most of which have been based on recent molecular discoveries. However, there are still some controversial issues that remain to be resolved, and some of them are discussed in this review.

Department of Pathology and Laboratory Medicine Arnie Charboneau Cancer Institute University of Calgary Calgary Canada

Department of Pathology and Molecular Genetics Bioptical Laboratory Ltd Pilsen Czech Republic

Department of Pathology Faculty of Medicine in Pilsen Charles University Pilsen Czech Republic

Sikl's Department of Pathology Faculty of Medicine in Pilsen Charles University E Benese 13 30599 Pilsen Czech Republic

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