Detection of residual disease with CT scan after surgery of juvenile nasopharyngeal angiofibroma

Abstract

Objectives: High recurrence rates have been reported for juvenile nasopharyngeal angiofibroma (JNA) involving the skull base. Early diagnosis and treatment of residual disease (RD) is a main determinant to prevent regrowth of the tumor. The purpose of this retrospective study was to evaluate the diagnostic accuracy of contrast-enhanced CT scan for the detection of RD in the early postoperative course after surgical excision of JNA. Methods: Based on an inception cohort of 20 boys who had a contrast-enhanced helical CT scan in the days following an apparently complete surgical excision of JNA with initial expansion in the skull base with a minimum of 2 years of follow-up, 4 independent, blinded readers evaluated the occurrence of RD. Final diagnoses were rendered based on results of histologic examination of excised specimens of RD or clinical and radiologic follow-up. The Cohen k test was performed to examine interreader agreement. Results: Postoperative contrast-enhanced CT scan had a sensitivity of 74%, a specificity of 98%, a positive predictive value of 97% and a negative predictive value of 82% for detection of RD. The prevalence of RD was 45%. Interreader agreement was high for detection of putative RD (k= 0.83). Conclusion: Contrast-enhanced helical CT scan performed in the days following surgical excision of JNA is an accurate tool to evaluate excision of JNA and to perform an additional endoscopic procedure if needed. Results of further studies are necessary to prove whether early postoperative contrast CT affects the optimal therapeutic management and high recurrence rate of JNA involving the skull base.