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Ultrasonographic Evaluation of Salivary Glands for Sjogren's Syndrome: Diagnostic and Monitoring Insights
Published on: October 13, 2023
Clinical manifestations of recurrent parotid pleomorphic adenoma
Myung-Whan Suh1, J Hun Hah, Seong Keun Kwon
1Department of Otolaryngology-Head and Neck Surgery, Dankook University, Cheonan, Korea.
Objectives:
This study was undertaken to confirm the clinical characteristics of recurrent pleomorphic adenoma (RPA), and to identify those factors that affect the development of malignant transformation (MT) from RPA.
Methods:
The medical records of 270 patients, who were operated upon for parotid PA, were retrospectively reviewed. The pathologic specimens of a selected series of 23 patients were reviewed for histologic subtype and microscopic multi-nodularity.
Results:
Mean age of initial operation in RPA without MT (RPA(-MT)) group was significantly lower than that of primary PA group. Mean age of the revision operation in RPA with MT (RPA(+MT)) group was significantly greater than that of RPA(-MT) group. Mean interval from operation to recurrence shortened after each revision operation. The risk of MT and additional recurrence increased significantly with recurrence. In RPA(-MT) group tumor recurrence occurred in 21.4% of patients despite a clear resection margin.
Conclusion:
The risk factors for MT may be an age of over 45 yr and multiple recurrences. However, younger patients are more at risk of recurrence. A clear resection margin cannot guarantee a cure in RPA, and it seems that parotid pleomorphic adenomas slowly gain malignant characteristics after repeated recurrences.
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