Objectives: There are no randomized trials to support the use of adjuvant radiation for adult head and neck sarcomas, therefore treatment trends vary between institutions. Positive surgical margins are a known risk factor for recurrence and poor survival outcomes in sarcoma treatment. This study uses the National Cancer Database (NCDB) and aims to investigate whether treatment with adjuvant radiation is associated with improved survival outcomes in adult head and neck sarcoma patients with a positive surgical margin.
Methods: There were 5,950 adult patients treated surgically for a head and neck sarcoma in the NCDB from 2004 to 2013 and 1,142 of these patients had a positive margin after surgical resection. There were 839 microscopic positive margins and 303 macroscopic positive margins. For patients with a positive margin, 969 patients were treated at academic/research cancer programs and 356 were treated at community-based cancer programs. 5-year overall survival (OS) was the primary outcome.
Results: Treatment with adjuvant radiation therapy was significantly associated with improved 5-year OS for all patients with a positive surgical margins (57% versus 48%; p=0.002), those with a microscopic positive margins (57% versus 49%; p=0.010), and those with a macroscopic positive margins (57% versus 41%; p=0.036) (Figures 1, 2, and 3, respectively). Improved OS was significant after controlling for other known covariates on multivariate analysis (HR 0.76; 95% CI 0.64 – 0.90, p=0.001). Patients treated at academic/research cancer programs were more likely to received adjuvant radiation for a positive surgical margin (60%) than those patients treated at community-based cancer programs (34%; p<0.001).
Conclusion: Adjuvant radiation therapy is associated with a significant survival benefit for adult head and neck sarcoma patients with both a microscopic and macroscopic positive surgical margin. Treatment at an academic/research cancer program was associated with increased utilization of adjuvant radiation for these patients.
Figure 1. Overall survival comparing patients that received adjuvant radiation therapy and those that did not in all patients with positive margins (p=0.002).
Figure 2. Overall survival comparing patients that received adjuvant radiation therapy and those that did not in patients with microscopically positive margins (p=0.010).
Figure 3. Overall survival comparing patients that received adjuvant radiation therapy and those that did not in patients with macroscopically positive margins (p=0.036).