Presentation and Outcomes of Non-Squamous Cell Carcinoma Sinonasal Malignancies: A National Perspective

Background: Non-squamous cell carcinoma sinonasal malignancies (NSCCSM) are relatively rare. Neoadjuvant radiotherapy and/or chemotherapy (NTx) have been proposed to improve outcomes compared to surgery alone. In this study, we aim to examine the prevalence of NTx utilization and associated outcomes. Methods: A retrospective study utilizing the National Cancer Database, 2004 to 2015. The study population included adult patients diagnosed with primary NSCCSM. Results: A total of 574 patients were included. The mean age of the study population was 61.7 +/- 16.5 years. The median follow-up time was 40.4 months (interquartile range: 15.3-81.3 months). The histopathological diagnoses identified included: (i) 37.0% adenocarcinoma, (ii) 22.8% adenoid cystic carcinoma, (iii) 20.0% mucosal melanoma, (iv) 11.9% esthesioneuroblastoma, and (v) 8.2% sinonasal undifferentiated carcinoma (SNUC). NTx was utilized in 70 (12.20%) of the study population. Patients who received NTx were more likely to have SNUC or esthesioneuroblastoma (P < .01 each) and to have stage III or IV disease (P < .01 each). NTx was most likely to be administrated in a high-volume center [OR: 3.94, 95%CI: (1.47, 10.53), P = .006]. Patients who received NTx had a significantly lower prevalence of positive margin postoperatively [OR: 0.48, 95%CI: (0.26, 0.87), P = .016]. In patients with NSCCSM, negative margin was associated with improved overall survival [HR: 0.55, 95%CI: (0.36, 0.82), P = .004]. Conclusions: This study provides an epidemiological perspective regarding NSCCSM and related practice patterns and survival outcomes. Neoadjuvant radiotherapy and/or chemotherapy is likely to decrease the risk of positive margin which ultimately could improve survival in this population.