Prognostic factors for secondary recurrence of pleomorphic adenoma: a 20-year, retrospective study

The mean age at diagnosis of primary pleomorphic adenoma recurrence was 43.4 years. Twenty-eight per cent of patients had secondary recurrence; 32 per cent had undergone two or more surgical resections and external adjuvant radiotherapy. An age of less than 25 years was significantly associated with an earlier primary recurrence (p = 0.008). The most significant histopathological risk factor for secondary recurrence was the presence of a multifocal tumour (p = 0.019). Other histopathological criteria (i.e. cellularity and capsule rupture) were not significant. Radiotherapy was not associated with a decrease in recurrence. Nine per cent of patients progressed to malignancy. The main surgical complication was definitive facial palsy (14 per cent).