Warthin's tumour: Aetiopathogenesis dilemma, ten years of our experience.

Despite the volume of studies written after the initial report by Hildebrand (1895) on Warthin's tumour (WT), its aetiopathogenesis continues to be an unresolved and controversial question. Many different genetic and/or environmental aetiological factors seem to act on heterotopic ductal inclusions and may give rise to WT following an unknown tumorigenic event. Recent studies discussed the importance of immunological reactions during the formation of the tumour. A hypersensitive/allergic reaction may play a role in epithelial proliferation and may stimulate the reactivity of the germinal centres in the lymphoid stroma as showed at histological examination. The aim of this study was to inform readers of the current understanding of possible risk factors with a suggested aetiological role in Warthin's tumorigenesis. From 2001 to 2011, a total of 342 patients with benign salivary neoplasm were admitted in the Department of Maxillofacial Surgery of the University of Naples "Federico II". A histological diagnosis of WT was made in 115 of the patients (33.6%); these were retrospectively investigated in our study. Correlation between the onset of WT and positivity for autoimmune diseases and smoking habits was calculated. The incidence rate of autoimmune thyroiditis in our series (9.5%) was significantly greater than that of the general population (0.58%) (p < 0.001). Analysis of our series and review of the literature support the hypothesis that this tumour is the result of an autoimmune reaction. Further studies and larger series are required to confirm this hypothesis and investigate the role of other aetiological factors in WT genesis.