Sinonasal intravascular papillary endothelial hyperplasia (Masson's tumor): report of a new patient with review of literature.

Objective: To provide the clinico-radiologic and histopathologic illustration of a unique case of sinonasal intravascular papillary endothelial hyperplasia (IPEH; Masson's tumor).

Methodology: Case report and review of literature.

Results: A 29-year-old man presented with right-sided nasal obstruction and occasional blood-tinged mucopurulence for two years. Diagnostic naso-endoscopy revealed a fleshy polypoid mass occupying the right nasal cavity encroaching into the nasopharynx. The mass was tender and firm, and bled on touch. Gadolinium-enhanced magnetic resonance imaging done two months prior showed a large, heterogenous mass in the right nasal cavity, partly involving the maxillary sinus, and extending into the nasopharynx. The findings were corroborated in a recent contrast-enhanced computed tomography scan that revealed mild contrast uptake and bone remodeling due to expansile nature of the mass without any erosion. An infected antrochoanal polyp, vascular tumor, and neoplastic lesions (including inverted papilloma) were considered as differentials. A subsequent punch biopsy revealed histologic pictures suggestive of IPEH. The mass was excised completely through endonasal endoscopic approach, and it was found to originate from the right inferior turbinate. The final histopathology confirmed the biopsy findings. Troublesome bleeding was encountered both during the biopsy and endoscopic excision of the mass. The patient is symptom-free with no recurrence at one-year follow-up.

Conclusions: Sinonasal IPEH (Masson's tumor) is an extremely rare entity; only 14 patients have been reported in the last four decades as evident from the PubMed/MEDLINE search. The present report adds to the existing literature, summarizes the clinico-radiologic and histopathologic perspectives, highlights the surgical challenges, and underlines the importance of having a low threshold of suspicion for considering this entity as a differential in a bleeding sinonasal mass.