Xenogeneic Collagen-Based Dural Substitute, A Stranger in Sinonasal Pathology.

Sinonasal mesenchymal neoplasms are challenging to classify due to their rarity. Xenogeneic collagen-based dural substitutes, such as DuraMatrix, are used for dural repair in sinonasal surgery, but their histologic features have been described only briefly in a few animal studies. When encountered in sinonasal specimens in the absence of a relevant surgical history, these materials may be mistaken for incidental mesenchymal neoplasms because of features such as intermixed spindle cells and a minimal foreign-body giant cell reaction. By detailing the histopathologic findings, we aim to facilitate recognition of dural substitutes among pathologists and avoid unnecessary diagnostic workup.