Salivary duct carcinoma presenting with vaginal metastasis: case report

Vaginal cancer represents about 1-2% of the genital tract malignancies. Most cases represent metastasis from the cervix, endometrium or colon. Metastasis of salivary duct carcinoma to the vagina has not been previously reported. Salivary duct carcinoma (SDC) is a rare, highly aggressive tumor that most often involves the parotid gland. On presentation, SDC is metastasized to the regional lymph nodes in about 40% of cases. We report a case of metastatic salivary duct carcinoma presenting as a vaginal mass with bleeding. Diagnosis was confirmed by the histological appearance in addition to immunohistochemistry. To our knowledge this is the first reported case of vaginal metastasis from SDC. Small-sized primaries might be ignored by the patient, specially in the older age group, probably due to lack of manifesting symptoms like pain and bleeding. Some cancers, like SDC, have various histologic patterns in different areas of the tumor. Careful examinations of multiple sections, in addition to an immunohistochemical panel, and histologic comparison of all lesions are keys to a correct diagnosis.