Peripheral giant cell granuloma

From Dog
Characteristic histopathological appearance of a giant cell granuloma[1]

Peripheral giant cell granuloma (Giant cell epulis) are a localized, benign exophytic growth on the gingiva of dogs[2].

Although the cause of these benign tumors is unknown, in humans there is a close relationship between giant cell granulomas and multinucleate cells to osteoclasts, suggesting that local periosteal inflammation or trauma may stimulate proliferation of mesenchymal progenitor cells leading to the formation of osteoclastic and osteoblastic cells[3].

Epstein-Barr virus and cytomegalovirus have also been isolated from these tumors in humans[4]. The former virus has been diagnosed plentifully over the years in dogs in close proximity to humans.

These tumors are commonly found in the rostral mandible, requiring it to be distinguished from other forms of epulis such as ameloblastoma.

Characteristic histological features are similar to those with giant cell tumor[5], with vascular gingival masses composed of large numbers of multinucleated giant cells in a background of mononuclear stromal cells. Areas of hemorrhage and hemosiderosis are also common[6].

Diagnosis requires histopathological analysis of biopsied material.

A differential diagnosis would include squamous cell carcinoma, followed by less common oral tumors such as bone cysts, dentigerous cyst and melanoma.

Treatment usually necessitates wide extirpation of the lesion or rim mandibulectomy.

References

  1. Granuloma
  2. Gardner DG (1996) Epulides in the dog: a review. J Oral Pathol Med 25(1):32-37
  3. Sapp JP (1972) Ultrastructure and histogenesis of peripheral giant cell reparative granuloma of the jaws. Cancer 30:1119
  4. Saygun I et al (2009) Human cytomegalovirus in peripheral giant cell granuloma. Oral Microbiol Immunol 24(5):408-410
  5. Trigo FJ et al (1983) A comparison of canine giant cell tumor and giant cell reparative granuloma of bone. Vet Pathol 20(2):215-222
  6. Desoutter AV et al (2012) Clinical and Histologic Features of 26 Canine Peripheral Giant Cell Granulomas (Formerly Giant Cell Epulis). Vet Pathol Mar 12