A Single-Arm, Prospective, Phase II Study of Cisplatin Plus Weekly Docetaxel as First-Line Therapy in Patients with Metastatic or Recurrent Salivary Gland Cancer

Purpose Salivary gland cancers (SGCs) are relatively rare but comprise various histologic subtypes, which complicates design of prospective trials. Systemic chemotherapy plays a limited role in treatment of SGCs, but cisplatin and docetaxel showed efficacy in a previous preclinical study. Here, we conduct a prospective, phase II study to evaluate the efficacy and toxicities of cisplatin plus weekly docetaxel in patients with metastatic or recurrent SGC.Materials and Methods We included patients with histologically confirmed SGCs of the following subtypes: mucoepidermoid carcinoma, adenocarcinoma, ductal carcinoma, or adenoid cystic carcinoma. Patients had no prior systemic chemotherapy for metastatic or recurrent tumors and at least one measurable lesion. Patients were treated with docetaxel 35 mg/m2 (D1, 8) and cisplatin 70 mg/m2 (D1) every 21 days.Results Forty-one patients were enrolled between April 2014 and October 2020. The median age was 58 years (range, 32 to 73 years). The most common histologic subtype was adenoid cystic carcinoma (63.4%), followed by ductal carcinoma (24.4%). The most common metastatic site was the lung (75.6%). The median treatment cycle was 5.5 (range, 3 to 8), and the objective response rate was 46.3%, with three complete responses. The median duration of response was 6.8 months (interquartile range, 4.0 to 10.2). The progression-free survival and overall survival were 9.4 months (95% confidence interval [CI], 8.4 to 10.5) and 28.2 months (95% CI, 22.7 to 33.6), respectively. There were no treatment-related deaths. The most common grade 3/4 adverse events were neutropenia (4.9%) and fatigue (4.9%).Conclusion Cisplatin plus weekly docetaxel is effective and tolerable with manageable toxicity as first-line therapy in patients with metastatic or recurrent SGC.