RESUMO
A fully developed tumor is the first manifestation of a typical salivary gland neoplasm. Identification of precursor lesions and the accompanying clinical findings may improve our understanding of these tumors. The frequency of possible precursor lesions of salivary gland tumors have not been systematically investigated to date. In this study, slides of 661 cases from three pathology laboratories in Ankara, Turkey were reviewed to search for possible precursor lesions. Salivary gland parenchymal changes adjacent to a variety of salivary gland disorders such as metaplastic changes, ductal epithelial hyperplasia, adenomatoid ductal hyperplasia, adenomatoid oxyphilic hyperplasia, adenomatoid hyperplasia of the minor salivary glands, myoepithelial sialadenitis and dysplasia were screened histologically as potentially precursor lesions. Nuclear protein Ki-67 and cellular tumor antigen p53 were also analyzed immunohistochemically in selected cases. Approximately 16% of the cases in this series contained various types of pathologic hyperplasia. Only a minority of these lesions were originally reported, so most of the findings in this study were not part of the original histology reports. The majority of these parenchymal changes were seen in parotids. Adenomatoid ductal hyperplasia was the most frequent possible precursor lesion, and it was found most frequently around pleomorphic adenomas. Although the biological significance of most of the lesions described in this report still remains to be understood completely, efforts to define and detect possible preneoplastic lesions should be intensified. We believe that detection and eradication of the precursors is the best way of decreasing the overall morbidity caused by salivary gland tumors.
RESUMO
BACKGROUND: Fibrous dysplasia (FD) is a maturation defect characterized by immature woven bones and stroma. However, especially in craniofacial bones, lamellation can be seen and this is associated with the maturation. AIM: To show maturation in FD and discuss the factors that may affect the maturation. MATERIALS AND METHODS: Ninety-five FD cases were divided into three subgroups according to the lamellation percentage as Groups 1, 2 and 3 (low, moderate and high lamellation, respectively). Each group was compared in terms of the peritrabecular clefting (PTC), stromal cellularity and the age. The lesions under pressure and the ones that are not were compared in terms of lamellation percentage. RESULTS: A significant statistical difference was found between Groups 1 and 3 in terms of PTC, stromal cellularity, histologic pattern suggesting maturation (p<0.001, p<0.001, p=0.002, respectively). CONCLUSION: The findings suggested a strong relation between lamellation and maturation. Lamellation was more prominent in the bones under pressure than the others. Considering lamellation as a finding of maturation, it is possible to establish a relation between maturation and pressure. Therefore, future studies should focus on the question if the pressure could be a factor for maturation and it could be used for treating FD.