title: [New therapy approaches for giant cell tumors].
abstract: BACKGROUND
  Giant cell bone tumors (GCT) are benign but partially locally aggressive osteolytic tumors which typically occur around the knee joint in the epiphysis and metaphysis of long bones after maturation of the skeleton is completed. Due to the locally aggressive growth behavior with destruction of the bone structure, the rare possibility of pulmonary metastases in recurrent cases and a very rare possibility of malignancy, GCTs were previously also described as semimalignant bone tumors.
  
  
  METHODS
  The established therapy of these tumors at the typical locations consists of intralesional curettage, extension of resection margins using a high speed trephine and defect reconstruction with bone cement. The local recurrence rate is high (10-40 %) and lowest after using thermal extension of resection margins with a high speed trephine and defect reconstruction with bone cement. For uncommon localizations, such as the spinal column and the sacrum as well as in cases of recurrence, surgical treatment is more complicated.
  
  
  RESULTS
  Histologically, GCTs consist of osteoclastic giant and oval-shaped stromal cells which show a high expression of receptor activator of nuclear factor-κB ligand (RANKL) and decisively contribute to the osteolytic activity of the tumor. Novel pharmaceutical therapy approaches with human monoclonal RANKL antibodies interfere in this osteodestructive process in an inhibitory manner and can represent alternative treatment options just as the osteosupportive therapy with bisphosphonates.
  
  
  CONCLUSIONS
  After unsatisfactory attempts at surgical treatment of GCT patients, the new treatment option with denosumab is a promising alternative due to its effect as a monoclonal RANKL inhibitor.
authors.affiliation: Chirurgie, Orthopädie und Unfallchirurgie, Rettungsmedizin, Klinik für Unfallchirurgie, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625, Hannover, Deutschland, Panzica.Martina@mh-hannover.de.
authors.forename: M
authors.initials: M
authors.lastname: Panzica
authors.forename: U
authors.initials: U
authors.lastname: Lüke
authors.forename: M
authors.initials: M
authors.lastname: Omar
authors.forename: F
authors.initials: F
authors.lastname: Länger
authors.forename: C
authors.initials: C
authors.lastname: v Falck
authors.forename: C
authors.initials: C
authors.lastname: Krettek
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001843:Bone Cements / Q000627:therapeutic use*; D001859:Bone Neoplasms / Q000000981:diagnostic imaging* / Q000628:therapy*; D003131:Combined Modality Therapy / Q000379:methods; D018212:Giant Cell Tumor of Bone / Q000000981:diagnostic imaging* / Q000628:therapy*; D006801:Humans; D019060:Minimally Invasive Surgical Procedures / Q000379:methods; D010027:Osteotomy / Q000379:methods*; D011859:Radiography
chemical_list: D000970:Antineoplastic Agents; D001843:Bone Cements