A Large Submucosal Mass With Prominent Superficial Vessels

Abstract

A man in his 40s presented with a multiple-year history of difficulty breathing throughhis left nostril. Severalmonthsprior topresentation, he began to experience left-sided epistaxis occurring up to 10 times per month, which was controlled with direct pressure. More recently, a friend noticed bulging of his left lateral nasal sidewall. Physical examination revealed a large submucosal mass with prominent superficial vessels within the mucosa almost completely filling the left anterior nasal cavity. Axial computed tomography (CT) showed a well-circumscribedoval-shaped lesionwith intermediate attenuation in the left anterior nasal cavity that shifted the septum to the right with remodelingof thenasalbone (Figure, A). The lesionhadmostlyhigh signalonaxialT2-weightedmagnetic resonance imaging(MRI)within which therewas a reticular pattern of septawith low signal (Figure, B). The lesionhadheterogeneous,mostly low signal on coronal fatsuppressed T1-weighted imaging (Figure, C), as well as prominent heterogeneous contrast enhancement using the same sequence (Figure,D).The lesionwas resectedviaanendoscopicendonasal approach andwas found to be originating from the left superior nasal septumwithnoextensionbeyond the left lateral nasalwallmucosa or the right septal mucosa. What is your diagnosis? A B