Carcinoma ex pleomorphic adenoma primarily composed of squamous cell carcinoma in buccal region – Case report

Abstract

Carcinoma ex pleomorphic adenoma (CXPA) is a tumor arising from a pleomorphic adenoma and classified as an independent type in the 2005 WHO classification. These tumors mainly occur in the parotid gland or palate, though rarely in the buccal region. The carcinoma component is most often a salivary duct carcinoma, while findings of a squamous cell carcinoma (SCC) are rare. Here, we report a case of carcinoma of pleomorphic adenoma origin with SCC as the main component occurring in the buccal region. A 77-year-old woman was referred to our department because of swelling in the right buccal mucosa. An elastic hard mass was found in the right buccal subcutaneous region and induration in the right buccal mucosa due to the mass was noted by palpation. Biopsy results from an obtained specimen led to a diagnosis of SCC. The patient underwent excision of a right-sided buccal malignant tumor in combination with skin resection and partial right-sided maxillary resection. Histopathological examination findings of the excised tumor indicated CXPA primarily composed of SCC with lymph node metastasis. Thereafter, multiple sites of distant metastasis were found. The patient died at two years six months after surgery.