Giant Cell Reparative Granuloma

Abstract

Giant cell reparative granuloma is a benign, reactive intraosseous process characterized by the presence of multinucleated giant cells, fibroblasts, and immature new bone formation in the absence of hyperparathyroidism. The lesion arises most commonly in the craniofacial skeleton and in small bones of the hands and feet. Although morphologically similar, lesions of the hands and feet have molecular findings akin to aneurysmal bone cysts and should be considered histogenetically apart from the jaw lesions. There is no sex predominance, and 75% occur in the first three decades of life, with a peak in the third decade. It is a solitary, radiolucent, expansive lesion located more frequently in the diaphysis or metaphysis; with evolution, it may extend to the epiphysis after growth plate closure. It presents a sharp margination. Histological features include giant cells that are commonly arranged in clusters. The giant cells are small, with few nuclei. Frequently, giant cells are seen around hemorrhagic zones. The stroma is formed by spindled mononuclear cells that produce collagen. Immature bone and osteoid reactive trabeculae lined by prominent osteoblasts are common features. The treatment consists of curettage and bone grafting.

Eduardo Santini-Araujo was deceased at the time of publication.