Relationship of intraoperative rupture of pleomorphic adenomas to recurrence: an 11-25 year follow-up study.

BACKGROUND

Intraoperative rupture of the capsule of a pleomorphic adenoma is reported to be associated with an increased recurrence rate. For many years, we have noted few recurrences among patients who experienced rupture of the capsule during surgery. Therefore, we asked "How often has surgical rupture of the capsule of a mixed parotid tumor resulted in recurrence among our patients?" This study is a summary of our clinical observations and not a methodologic one.

METHODS

The medical records of 346 patients operated on between 1965 and 1981 were reviewed. The surgical notes and histopathologic descriptions were examined with special reference to the relationship between surgical margins and tumor capsule. Satisfactory follow-up was obtained from 238 patients primarily operated on in our department. The average observation time was 18 years. None of our patients received postoperative irradiation.

RESULTS

Six (2.5%) patients had a recurrence 7 to 18 years postoperatively (mean 11.8 years). This recurrence rate is of the same order of magnitude as other reports. Rupture of the capsule with macroscopic spillage of tumor cells occurred in 26 patients and two (8%) of them developed recurrent tumors. Surgical dissection close to the capsule was performed in 87 cases, with one recurrence. In the remaining 121 patients the surgical dissections were done without visualizing the tumor capsule. Three (2.5%) of these cases developed recurrent tumor. The 8% recurrence rate after capsule rupture is not statistically different from the 2% for the other patients. There was also no difference in recurrence rate between patients with microscopic positive or negative surgical resection margins.

CONCLUSIONS

We question whether spillage of tumor cells from a pleomorphic adenoma plays such an important role in the development of recurrent tumors as has been previously postulated. We also question the justification and benefit of postoperative radiotherapy for patients with this benign disease.