title: Extramedullary hematopoiesis: a rare occurrence in the sinonasal tract.
abstract: Extramedullary hematopoiesis (EMH) is a systemic reaction to inadequate hematopoiesis. We report two exceedingly rare cases of EMH involving the paranasal sinuses. The first patient, a 30-year-old man, presented with a maxillary sinus mass. The lesion was excised by endoscopic surgery: definitive histology identified foci of EMH within an inflammatory fibromyxoid pseudotumor. The second case occurred in a 29-year-old man affected by intermediate beta-thalassemia. He was hospitalized with a diagnosis of sphenoid sinus mucocele secondary to an ethmoid lesion. The patient underwent endoscopic excision of the mass and drainage of the sphenoid mucocele. At definitive histology, a diagnosis of EMH was established. Herein, the presenting modalities, imaging profile, and treatment options of this rare EMH localization are reviewed.
authors.affiliation: Department of Otorhinolaryngology, University of Brescia, Piazza Spedali Civili 1, Brescia, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Bizzoni
authors.forename: Davide
authors.initials: D
authors.lastname: Lombardi
authors.forename: Roberto
authors.initials: R
authors.lastname: Maroldi
authors.forename: Paolo
authors.initials: P
authors.lastname: Incardona
authors.forename: Piero
authors.initials: P
authors.lastname: Nicolai
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D004724:Endoscopy; D005005:Ethmoid Sinus / Q000473:pathology / Q000503:physiopathology*; D005350:Fibroma / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D006104:Granuloma, Plasma Cell / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D006411:Hematopoiesis, Extramedullary / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008443:Maxillary Sinus / Q000473:pathology / Q000503:physiopathology*; D008444:Maxillary Sinus Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D010254:Paranasal Sinus Diseases / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D013101:Sphenoid Sinus / Q000473:pathology / Q000503:physiopathology*; D014057:Tomography, X-Ray Computed