Carcinoma ex pleomorphic adenoma of the parotid gland: a case with difficult diagnosis

Carcinoma ex pleomorphic adenoma (CXPA) is carcinoma arising from a primary or recurrent benign pleomorphic adenoma. It might be non-invasive or invasive. It often poses a diagnostic challenge to clinicians and pathologists. Pathological assessment is the gold standard for diagnosis. Treatment for CXPA often involves an ablative surgical procedure, which may be followed by radiotherapy. We report to you a 63-year-old female who came to the ENT OPD with a complaint of swelling in the front of the right ear for 6 months and pain over swelling for 2 weeks. The patient was advised for USG-guided FNAC, which was suggestive of a benign cystic parotid lesion. The patient was planned for superficial parotidectomy and the tumor was surgically excised. The frozen section was suggestive of a benign salivary gland tumor and the histopathology report concluded of a non-invasive carcinoma ex pleomorphic adenoma. The patient was advised to undergo radiotherapy after the surgery. During the follow-up, the patient showed signs of Frey’s syndrome. Carcinoma ex pleomorphic adenoma is difficult to diagnose; clinicians and pathologists should work together to diagnose it and pathological assessment is the gold standard for the diagnosis.