Endoscopic Management of Inverted Papilloma Using CT Scan as the Predictor of Tumour Origin

Abstract

Introduction
 Inverted papillomas are notorious for recurrence. The surgical cause attributed to recurrence is failure to achieve good surgical exposure and inadequate clearance of disease. Pre-operative prediction about the site of origin by CT Scan may contribute to a better surgical outcome. This study was undertaken to assess if focal hyperostosis on pre-operative CT scan can be considered to be a predictor of the site of tumour origin and correlate with endoscopic finding of the site of origin.
 Materials and Method
 A prospective descriptive study was carried out between Jan 2014 and May 2016. Fifteen patients of histopathologically proven inverted papilloma that reported during this time period were evaluated using contrast enhanced CT Scan and subsequently underwent endoscopic excision of tumour identifying the tumour origin. Assessment of age, gender, symptoms, pre-operative staging, location of the tumour origin on CT Scan and surgical correlation of origin was done. Post-operative follow-up was done at 1 month, 3 months and 6 monthly thereafter.
 Results
 Six (40%) were classified as Krouse II and nine (60%) were classified as Krouse III. 12 (80%) arising from maxillary sinus, 02 (13.3%) arising from maxillary sinus and anterior ethmoids and 01 (6.7%) from sphenoid. Thirteen (86.7%) cases CT scan could predict the tumour origin which was confirmed during surgery. All cases managed by endoscopic technique with no recurrence or co-existence of malignancy.
 Discussion
 Focal hyperostosis in the walls of paranasal sinus is seen to be associated with IP tumour origin, the cause of which is not fully understood. It is hypothesized that tumour induced inflammation at the site of origin leads to bone remodeling and increased bone deposition with vascularity at the site of attachment.
 Conclusion
 CT scan is a good predictor of tumour origin and a conservative endoscopic approach can be planned accordingly for complete clearance of disease.