Cytomorphology of Sinonasal Glomangiopericytoma: A Rare Case and Review of Literature

Sinonasal glomangiopericytoma is a mesenchymal neoplasm of pericytic derivation with characteristic CTNNB1 gene mutation usually arising from the sinonasal cavity. Given its monomorphic and cellular morphology, it can mimic mesenchymal, epithelial, or even lymphoid neoplasms. Reports highlighting the cytology of sinonasal glomangiopericytoma have not been, to our knowledge, documented yet. Herein, we shed light on the cytomorphology of a rare case of sinonasal glomangiopericytoma arising in the ethmoid sinus of a 77-year-old male, review the literature, and discuss the differential diagnosis of such a challenging entity.