CARCINOMA-EX- PLEOMORPHIC ADENOMA ARISING WITHIN A PALATAL MINOR SALIVARY GLAND: A CASE REPORT AND REVIEW OF...

Carcinoma-ex-Pleomorphic Adenoma (CXPA) is a malignant tumour originating from the epithelial components of a primary or recurrent Pleomorphic Adenoma (PA). The minor salivary gland of the palate is not a common site of occurrence of this tumour. Approximately 6% of pleomorphic adenomas have the potential to transform into carcinoma ex pleomorphic adenoma (CXPA). It is typically a high-grade tumour and disease-related death is often being seen due to distant metastases.

A 52-year-old man presented with seven years history of a painless palatal mass which started insidiously and progressively increased in size over the years. There was no history of trauma, toothache, and no history of swelling in other body parts. His medical history was not significant for any disease and no history of irradiation or surgery. Examination of the oral cavity revealed a non-ulcerated palatal swelling, measuring 10x8x5cm, non-tender, firm, not freely mobile, and adherent to the underlying structures.

An ovoid tan brown firm tissue was received which measured 9x7x5cm and weighed 140g. Transections show yellow-white homogeneous to nodular areas. Microscopy showed co-existence of a pleomorphic adenoma with an area of transition to a carcinoma.

Pathological assessment is the gold standard for making a diagnosis and the main histopathological finding in CXPA is the co-existence of the benign characteristics of pleomorphic adenoma with malignant changes in the epithelial components of the tumour.