Chemoradiotherapy versus radiotherapy in high risk salivary gland cancer.

Objective: The aim of this study was to investigate the potential survival benefits associated with chemoradiotherapy (CRT) as opposed to radiotherapy (RT) in patients with resected high-risk salivary gland cancer (SGC), with a specific focus on determining whether these benefits are influenced by the number of high-risk variables.

Methods: Patients who underwent surgical treatment for high-risk SGC were retrospectively enrolled and categorized into either CRT or RT groups. The impact of adjuvant therapy on locoregional control (LRC) and overall survival (OS) was assessed using a multivariable Cox model.

Results: A total of 152 patients were included following propensity score-matching. In comparison to RT, CRT did not demonstrate a significant survival advantage in terms of LRC (p = 0.485, HR: 1.14, 95%CI: 0.36-4.22) and OS (p = 0.367, HR: 0.99, 95%CI: 0.17-3.87) in entire population. But among patients with T3/4 stage, high-grade tumors, and 5 or more positive lymph nodes, the addition of chemotherapy to RT significantly (p = 0.042) correlated with a 15% reduction in the risk of cancer recurrence (95%CI: 4-54%). Conversely, in other subgroups with varying combinations of high-risk variables, CRT did not provide additional survival benefits for LRC and OS compared to RT.

Conclusion: Adjuvant chemotherapy may be considered in conjunction with RT specifically in cases where there is a presence of T3/4 stage, high-grade tumors, and 5 or more metastatic lymph nodes in high-risk SGC.