Treatment of Locally Advanced and Metastatic Salivary Gland Cancer: A 10-year Experience of an Oncology Center in Portugal.

Introduction: Scientific evidence regarding salivary gland cancer systemic treatment is limited and the therapeutic approach to locally advanced or metastatic disease is mainly based on consensus. This study aimed to evaluate treatment patterns and outcomes in patients with advanced salivary gland cancer.

Methods: We conducted a retrospective cohort study in a comprehensive cancer center in Portugal, including adult patients diagnosed with primary malignant salivary gland tumors between 2012 and 2021. Data on demographics, tumor characteristics, treatments, and outcomes were collected from institutional cancer registries and electronic medical records. The study was approved by the institutional Ethics Committee.

Results: A total of 116 patients with salivary gland cancer were identified and, of these, 45 had locally advanced or metastatic disease: 24 received systemic anti-neoplastic treatment and 21 received best supportive care. One-year overall survival in systemic anti-neoplastic treatment group was 70% (versus 14% in best supportive care group, p < 0.001) and progression-free survival was 37%. The most commonly used systemic treatment was chemotherapy (n = 29, 59%). Seven patients (14%) received androgen deprivation therapy, and two patients (4%) received other targeted therapy (olaparib and erdafitinib).

Conclusion: Systemic treatment was associated with significantly improved survival in patients with advanced salivary gland cancer. Despite the heterogeneity of therapeutic approaches, including emerging biomarker-driven therapies, clinical decision-making remains largely consensus-based. These findings underscore the need for further research to support personalized treatment strategies and guide evidence-based care.