Salivary duct carcinoma (SDC) is a very rare tumor, especially originating in the submandibular gland. We encountered two patients with SDC arising from the submandibular gland.
A 59-year-old man was referred to our institute with a complaint of a firm, fixed submandibular mass on the right side. The mass was resected with the surrounding tissue and diagnosed by pathologic examination as SDC. Radiotherapy of 66 Gy was done after the surgical procedure. Seven months after the initial resection, a 2.0-cm-diameter mass was noticed in the lower lobe of the left lung. A lower lobectomy was performed, and the pathologic examination showed recurrent metastasis from the SDC. Three years after lobectomy, he remains in good condition with no evidence of disease.
The other patient was a 52-year-old man who complained of a right neck swelling. A submandibular tumor was resected with the surrounding tissue and total neck dissection was performed. Histological examination revealed that the tumor presented with papillary and cribriform patterns with comedo necrosis. Because no tumor close to the cut-end and no positive lymph node were detected, postoperative therapy was not performed. Thirty months after the surgery, the patient remains alive without any evidence of recurrence.