Histological reclassification of 101 intraoral salivary gland tumours (new WHO classification).

The epithelial salivary gland tumours have for many years been categorised according to the 1972 World Health Organisation (WHO) classification. In 1990 a proposed revision of this classification was elaborated. In this study 101 intraoral salivary gland tumours were reclassified accordingly. In 29 of the cases the original histological diagnosis was changed, which in most cases, occurred in the benign or malignant tumour groups. In seven cases the diagnosis was changed from benign to malignant or vice versa. The results of this study show that the histological classification of intraoral salivary gland tumours remains difficult, even when applying the new WHO classification.