Pathogenesis (disease development)
Giant cell tumor is one of the histiocytic bone tumors. It consists of large, multinucleated osteoclast-like giant cells, to which it owes its name. Between these giant cells lie the actual tumor cells, namely mesenchymal mononuclear fibroblast-like cells.
The mononuclear cells produce large amounts of the so-called RANK ligand (Receptor Activator of NF-kB ligand). This is a protein from the tumor necrosis factor family that is involved in the regulation of bone remodeling. It ensures that bone resorption is in balance with bone formation. Tumor cells secrete (release) RANK ligand in an unregulated manner, leading to increased bone resorption as well as activation of giant cells.
Etiology (causes)
The exact causes of giant cell tumor are still unclear.
