Inverted Schneiderian papilloma
Inverted sinonasal or Schneiderian papilloma shows endophytic or “inverted” growth pattern (top left).
These nests of squamous epithelial cells grow down into the myxomatous to fibrous stroma with chronic
inflammatory cells and vascularity (top right and bottom left). Epithelial component shows many clear
cells suggestive of glycogen presence, and maintains polarity and nuclear uniformity (bottom right).
1 minute clinical correlation