LAUSR

Abstract Background/Aim: There is significant variation in post-treatment surveillance imaging for sinonasal malignancies. This study examined the utility of surveillance imaging in detecting recurrence in patients treated for sinonasal malignancies. Patients and Methods: We performed a retrospective review on an IRB-approved dataset of patients with sinonasal malignancies treated at a single institution between 2005 to 2021. Patients were categorized into groups based on the frequency of annual imaging and total number of imaging studies. We compared time-to-recurrence between the groups using log-rank test. A two-sided p-value of <0.05 was considered as the threshold for significance. Results: A total of 93 patients were eligible for this study with a median follow up of 42.3 months and 25.8% (n=24) of patients had documented recurrence. Sensitivity and specificity for recurrence based on computed tomography (CT) scans within one year of treatment completion were 50.0% and 19.5%; positron emission tomography/CT was 90.0% and 19.5%; and magnetic resonance imaging was 60.0% and 61.0%, respectively. Regardless of the type of imaging, symptomatic presentation after treatment had a specificity of 91.0% with a positive likelihood ratio of recurrence of 2.95 (95%CI=1.06-8.22). The frequency of scans was not associated with the risk of recurrence (HR=0.55; 95%CI=0.23-1.29, p=0.17). Similarly, no association was noted between the total number of scans and risk of recurrence (HR=0.64; 95%CI=0.27-1.51, p=0.31). Conclusion: The total number of frequency of scans within the first year after treatment had no association with time to recurrence of sinonasal malignancies. Symptomatic presentation was strongly associated with recurrence and should be investigated with appropriate imaging.