Salivary Duct Carcinoma Arising from a Minor Salivary Gland in the Oral Floor: Case Report, Immunohistochemical Observations, and Review of the Literature

Salivary duct carcinoma is a rare aggressive malignancy occurring most often in the parotid gland and less commonly in the minor salivary glands. This report describes a patient with salivary duct carcinoma originating from the oral floor. A 60-year-old Japanese woman presented with a painless mass on the left oral floor for 1 month. The tumour was diagnosed as a salivary duct carcinoma. At the 5-year follow-up, the patient remains in good health and free of disease.