Inflammatory fibroid polyp (IFP) is a benign abnormal growth of tissue projecting into the lumen of the gastrointestinal tract.High mag. Inflammatory fibroid polyp (IFP) is a benign abnormal growth of tissue projecting into the lumen of the gastrointestinal tract. IFPs consist of spindle cells that are concentrically arranged around blood vessels and have inflammation, especially eosinophils.They may have leiomyoma/schwannoma-like areas with nuclear palisading. They typically stain with CD34 and vimentin, and, generally, do not stain with CD117 and S100. The endoscopic differential diagnosis includes other benign, pre-malignant and malignant gastrointestinal polyps.