[A case report of giant cell granuloma of the jaw]

A giant cell granuloma of the mandible seen in a 16 month-old boy was reported. Histopathology showed that the lesion consisted basically of granulation tissue with multinucleated giant cells, spindle-shaped and polygonal stromal cells. No atypia was seen in giant cells or stromal cells. Electron microscopic examination revealed that multinucleated giant cells possessed microvillous structure on their cytoplasm and were rich in organelles such as endoplasmic reticulum, mitochondria and dense bodies. Stromal cells consisted of macrophage-like and fibroblastic cells. Immunohistochemical examination demonstrated a large number of giant cells and stromal cells that were strongly positive for the antibodies of alpha-1-antitrypsin and alpha-1-antichymotrypsin. These morphological findings suggest that macrophage-like stromal cells are the precursors to giant cells.