Carcinoma ex Pleomorphic Adenoma in the Parapharyngeal Space

Abstract

Objective: To present a case of carcinoma ex pleomorphic adenoma in the parapharyngeal
 space and discuss its management.
 
 Methods:
 Design: Case Report
 Setting: Tertiary Government Teaching Hospital
 Subjects: One
 
 Results: A 40-year-old male patient with dysphagia for three months and a left-sided mucosa-covered oropharyngeal mass was found to have a prestyloid parapharyngeal lesion on CT Scans. Fine Needle Aspiration Cytology (FNAC) revealed a pleomorphic adenoma. With a past history of parapharyngeal pleomorphic adenoma excised transorally three years before, the present mass was excised by mandibular swing approach. Post-operative recovery was uneventful, but the final histopathological report was carcinoma ex pleomorphic adenoma.
 
 Conclusion: Malignant transformation should be suspected in recurrent salivary tumors in the parapharyngeal space. Provided there was truly no pre-existing malignant focus in the originally-excised tumor, and that early recurrence was not due to inadequate initial excision, this patient had a rare condition where the same tumor underwent malignant transformation within 3 years only. To the best of our knowledge, such an early transformation to malignancy of a minor salivary gland tumor of the parapharyngeal space has not been reported in the English literature.
 
 Keywords: carcinoma ex pleomorphic adenoma, pleomorphic adenoma, carcinoma, parapharyngeal space, malignant, transformation, minor salivary gland tumor, mandibular swing