Page 19 - New epidemiological and PSMA-expression based paradigms in salivary gland tumors

Figure 6: A PSMA PET/CT scan showing the major salivary glands (Parotid, PG; Sublingual, SL; Submandibular, SM), minor glands in the nose / nasopharynx and the lacrimal glands (LG), as published by Klein Nulent, Valstar, et al. in Chapter 7 [9].
Despite the fact that the SGPA is by far the most frequent salivary gland tumor and has a malignant potential, its epidemiology had never been investigated on a nationwide scale. It meant that there was no optimal insight in the risk of recurrence and malignant transformation. We aimed to provide such an insight in Chapter 2, by presenting the results of a nationwide study on the incidence of salivary gland pleomorphic adenoma, risk of recurrence and malignant transformation and risk factors for recurrence in the Netherlands. The findings in our study and a similar study that was conducted almost parallelly in Denmark, made us wonder whether a pattern could be discerned in behavior of recurrent pleomorphic adenomas in the published literature. Chapter 3 presents the natural history of the recurrent pleomorphic adenoma, described in a systematic review and meta-analysis of the Danish and Dutch nationwide studies in an international collaboration. By combining data from these studies, a more detailed picture from rare events such as malignant transformation could be provided.
The concept of this process of a benign tumor turning malignant has been described by various reports showing small and large pieces of the puzzle. As an
General introduction and outline of this thesis
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