Temporal patterns of 18F-fluorodeoxyglucose positron emission tomography/computed tomography sinonasal uptake after treatment of sinonasal malignancy

• Published in: International forum of allergy & rhinology 2016-12, Vol.6 (12), p.1301-1307
• Main Authors: Schwartz, Joseph S., Brooks, Steven G., Stubbs, Vanessa, Ghosh, Ankona, Tajudeen, Bobby A., Khalili, Sammy, Palmer, James N., Lee, John Y.K., Nabavizadeh, Seyed Ali, Learned, Kim O., Adappa, Nithin D.
• Format: Article
• Language: English
• Subjects: endoscopic skull base surgery; esthesioneuroblastoma; Key Words; PET/CT; postoperative surveillance; sinonasal malignancy; Tomography
• ISSN: 2042-6976; 2042-6984
• DOI: 10.1002/alr.21814

Background Current guidelines have identified 10 to 12 weeks posttreatment as the ideal time‐point for improved diagnostic accuracy of positron emission tomography/computed tomography (PET/CT) for deep tissue sites of the head and neck. After treatment, the sinonasal skull base is predisposed to prolonged inflammation that may render this time‐point inappropriate for initial posttreatment imaging surveillance for sinonasal malignancies. The purpose of this study is to evaluate temporal trends in 18F‐fluorodeoxyglucose (18FDG) sinonasal uptake after treatment for sinonasal malignancies to better elucidate the optimal time‐point for initial PET/CT posttreatment evaluation in this patient population. Methods A retrospective analysis of all successfully treated and non–locally recurrent sinonasal malignancies over a 15‐year study period (2000 to 2015) was performed at our institution. Posttreatment 18FDG PET/CT standardized uptake value data were collected and compared between various time‐points (2 to 4 months, 5 to 12 months, 5 to 24 months, and 13 to 24 months) using an independent‐samples t test. Results A statistically significant difference was noted between the posttreatment time windows 2 to 4 and 5 to 12 months (p = 0.048) as well as 2 to 4 and 5 to 24 months (p = 0.02). A trend toward significance was seen when comparing 2 to 4 and 13 to 24 months (p = 0.083). Conclusion Our analysis of PET/CT in patients previously treated for sinonasal malignancy suggests that the posttreatment sinonasal skull base is characterized by a prolonged period of hypermetabolism that endures beyond the period previously described for deep tissue sites of the head and neck. These findings prompt a reevaluation of the previously described 10‐ to 12‐week cutoff point for initial posttreatment PET/CT for head and neck squamous cell carcinoma as applied to sinonasal malignancies.