Factors influencing the occurrence of multicentric and 'recurrent' Warthin's tumour: a cross sectional study.

The multicentric nature of Warthin's tumour has been well recognised, though the factors predicting its occurrence and its influence on management remain speculative. In this cross sectional study, the authors analysed the presentation, management and outcome of solitary and multicentric Warthin's tumour, treated in the maxillofacial unit and investigated factors that could influence the occurrence of multicentric and recurrent tumours. Warthin's tumour was found in 24% (150/628) of patients presenting with parotid neoplasms and multicentric tumours were found in 13% (21/ 161) of parotidectomy specimens. Age, sex, side, site and smoking history were not predictors of multicentricity (P>0.40). Clinical examination (19%), imaging investigations (28%) and intra-operative palpation (33%) were poor at detecting multicentric tumours. Superficial parotidectomy was the most commonly performed operation. The recurrence rate was 0% in the solitary and 10% in the multicentric tumour group. Intra-operative rupture was not uncommon (11%), but was not associated with tumour recurrence (P= or >0.999). Incomplete excision (P=0.007) and multicentricity (P=0.026) were predictors of recurrence.