Salivary duct carcinoma (SDC), which is a rare and aggressive tumor of the salivary glands, is associated with a high likelihood of development of distant metastasis and local recurrence even from an early stage of the disease. No effective treatment for metastatic SDC has been established yet. Immunohistochemical studies have demonstrated the expression of androgen receptors (AR) at a high frequency in cases of SDC, and we considered that endocrine therapy targeting AR would be effective for cases of SDC. We present the case of an 81-year-old man with AR-positive submandibular gland SDC, with neck lymph node and multiple bone metastases. We judged that radical resection would be difficult, and initiated the patient on anti-androgen therapy with oral bicalutamide. After 5 months of bicalutamide treatment, PET-CT showed obvious decrease in the size of the submandibular gland tumor, neck lymph node metastases, and bone metastases. The patient was continued bicalutamide treatment for more than 12 months.
Bicalutamide treatment should be considered for patients with AR-positive SDC.
