Inflammatory fibroid polyp of the gastrointestinal tract: possible origin in myofibroblasts? A study of twelve cases.

Inflammatory fibroid polyp (eosinophilic granuloma) is a rare benign condition found in the gastro-intestinal tract. Approximately 200 cases have been described in the literature. It is generally considered as a granulation tissue of a peculiar type; however its cellular composition remains controversial. Either macrophages, fibroblasts or myofibroblasts have been proposed as its main cellular constituents. A retrospective study of 12 cases (8 gastric and 4 intestinal locations) based on histology, immuno-histochemistry and electron microscopy, would suggest that this condition is truly a peculiar type of granulation tissue made up primarily of myofibroblasts.