Fibroid polyps of intestinal tract are inflammatory-reactive proliferations of CD34-positive perivascular cells

Histopathology. 1998 Jun;32(6):498-502.


Aims: Our aim was to determine the histogenesis of fibroid polyps (FP). These polyps are rare inflammatory-reactive, tumour-like lesions of unknown aetiology, arising in the submucosa or mucosa of the gastrointestinal tract. They are mainly due to a proliferation of characteristic spindle cells.

Methods and results: Nine FP were investigated by light microscopy and immunohistochemistry with endothelial markers (Factor VIII, CD34, CD31), a neuronal marker (S100), muscular markers (desmin, alpha-smooth muscle actin) and histiocytic markers (PGMI, KP1, MAC387) using the highly sensitive avidin-biotin-peroxidase technique. We demonstrate, for the first time, a consistent positivity of the characteristic spindle cells of FP for CD34. The proposed endothelial, histiocytic or neuronal origin of FP could be completely ruled out.

Conclusions: Because of the consistent positivity of the spindle cells of FP for CD34 we suggest an origin of these lesions from primitive perivascular or vascular cells. This origin and a probable relationship to gastrointestinal stromal tumours (GIST) is discussed.

MeSH terms

  • Actins / analysis
  • Antigens, CD34 / analysis*
  • Biomarkers / analysis
  • Desmin / analysis
  • Humans
  • Immunoenzyme Techniques
  • Intestinal Mucosa / blood supply
  • Intestinal Mucosa / immunology
  • Intestinal Mucosa / pathology
  • Intestinal Polyps / blood supply
  • Intestinal Polyps / chemistry
  • Intestinal Polyps / immunology*
  • Intestinal Polyps / pathology
  • Platelet Endothelial Cell Adhesion Molecule-1 / analysis
  • S100 Proteins / analysis


  • Actins
  • Antigens, CD34
  • Biomarkers
  • Desmin
  • Platelet Endothelial Cell Adhesion Molecule-1
  • S100 Proteins