Objectives: Capsular ruptures play a major role in recurrences of parotid pleomorphic adenomas. The aim of this retrospective study was to define histomorphological characteristics of pleomorphic adenoma in order to define possible recurrence mechanisms and to set a clear surgical management.
Material and method: Histological study was performed after reviewing of slides originating from 100 patients with pleomorphic adenomas of the parotid gland. These patients were treated in our institution during the period May 1992 - November 2002.
Results: The studied population was distributed into 3 histological subtypes for better analysis. Hypocellular (stroma rich) pleomorphic adenoma was reported in 56%, hypercellular pleomorphic adenoma was reported in 29% and "classic" in 15%. Thinness of capsule was significantly related to hypocellularity. Pseudopodias and satellite nodules were reported in 72% of this series.
Conclusion: Due to capsular characteristics, surgical excision should avoid dissection in the vicinity of the tumor in order to avoid capsular bare area, so minimizing the risk of surgical induced recurrence. According to these findings, enucleation surgery for pleomorphic adenoma should not be performed anymore. Parotidectomy techniques (total or lateral) constitute the surgical procedures of choice.