CARCINOMA EX PLEOMORPHIC ADENOMA OF THE SOFT PALATE

A case of carcinoma ex pleomorphic adenoma arising in the soft palate is reported. The tumor presented had enlarged gradually over 10 years and finally occupied the oral cavity. The patient was admitted to our hospital due to disturbance of her speech and swallowing, and a sudden haemorrhage from the tumour. The initial pathological diagnosis by op en biopsy was benign pleomorphic adenoma. After total resection, histo logical examination revealed that the tumour was composed partly of be nign pleomorphic adenoma and partly of an adenocarcinomatous component . The carcinoma cells with prominent nucleoli were spheroid or polygon al in shape, and frequently formed ductal structures with areas of nec rosis. Mitoses were also found. These findings showed that this tumour was a secondary carcinoma which had developed in a preexisting pleomo rphic adenoma.