Combination Chemohormonal Therapy in Metastatic Salivary Duct Carcinoma

BACKGROUND Salivary duct carcinoma (SDC) is a rare, aggressive head and neck cancer with frequent metastases. Current treatment options for recurrent or metastatic SDC include targeted anti-androgen therapy, HER2-targeted therapy, or systemic chemotherapy. We report the first use of a combination chemohormonal strategy. CASE REPORT A 68-year-old male who had never smoked with a past medical history of two-vessel coronary artery disease and systolic heart failure presented with a parotid mass and underwent surgical resection. Biopsy of the mass revealed high-grade, androgen receptor-positive and Erb-B2 receptor tyrosine kinase-2 (ERBB2)-amplified positive SDC. He subsequently received adjuvant radiation therapy. Four months after completion of adjuvant radiation therapy, recurrence with symptomatic pleural effusion and nodes, hepatic metastases, and boney metastases occurred. Due to significant symptomatic tumor, a rapid treatment response was desired. Combination chemohormonal therapy (CHT) was initiated with carboplatin area under the curve 4 and paclitaxel, 200 mg/m² in 21-day cycles along with combined androgen blockade using leuprolide, 45 mg subcutaneously every 6 months and bicalutamide, 50 mg daily. The treatment was well tolerated with fatigue as the main adverse event. Positron emission tomography-computed tomography at 3 and 6 months after treatment initiation showed good partial response. The patient experienced uveal progression after 8 months and alternate treatment was started. CONCLUSIONS Combination CHT with carboplatin, paclitaxel, and combined androgen deprivation may be a good treatment option in androgen receptor-positive recurrent or metastatic SDC if rapid treatment response is desired. Combination chemotherapy with androgen deprivation for validation through clinical trials.