Stensen's Duct Carcinoma with a Papillary Architecture.

Primary carcinoma of the parotid duct (Stensen's duct carcinoma) is a rare entity, first described in 1927 and with approximately thirty-one cases reported in the English literature. Criteria for diagnosis are primarily demonstration of an origin from the Stensen's duct lining and exclusion of parotid gland, accessory parotid, oral mucosal and adjacent minor salivary gland origin. The carcinoma is usually of a specific type, and most have been described as squamous, mucoepidermoid, or undifferentiated adenocarcinomas. We report an unusual case of Stensen's duct carcinoma showing a primarily basaloid phenotype with focal squamous differentiation and a partial papillary architecture raising the possibility of malignant transformation in a ductal papilloma. Wide local excision was performed with postoperative radiotherapy and the patient is free of complications one and a half years postoperatively. Due to the small number of cases reported, the overall prognosis is not well defined, but seems to depend on the tumour size. Regional metastasis confers a 14 % mortality rate but there appears to be no relationship between histological type and prognosis.