title: Sustained long-term complete regression of a giant cell tumor of the spine after treatment with denosumab.
abstract: BACKGROUND
  Although giant cell tumors (GCTs) are histologically benign, they may become locally aggressive bone tumors. As these lesions tend to respond poorly to radio- and chemotherapy, currently the standard surgical paradigm for the treatment of spinal GCTs involves en bloc surgical resection. Denosumab is a newly developed monoclonal antibody designed to inhibit the receptor activator of nuclear factor kappa-B ligand (RANKL) which has already been demonstrated to induce marked radiographic responses on GCTs of the appendicular skeleton. Nevertheless, the role of denosumab in the treatment algorithm of GCTs of the spine has not yet been defined.
  
  
  OBJECTIVE
  To describe the first case of sustained long-term complete clinical and radiographic regression of a GCT of the spine after treatment with the new RANKL antibody denosumab.
  
  
  METHODS
  Case report and literature review.
  
  
  METHODS
  The authors describe the case of 22-year-old female patient, harboring a GCT involving the C2 vertebral body and odontoid process, who was treated in monotherapy with denosumab, resulting in complete long-term clinical and radiographic tumor remission.
  
  
  RESULTS
  There were no major side effects associated with the long-term pharmacological treatment with denosumab. From the clinical standpoint, the patient demonstrated complete remission of the disease while under treatment. The 16-month radiographic follow-up demonstrated complete disappearance of the osteolytic process and intense new cortical bone formation with restoration of the bone integrity of the C2 vertebral body.
  
  
  CONCLUSIONS
  This is the first report of sustained long-term complete clinical and radiographic regression of a GCT of the spine after treatment with the new RANKL antibody denosumab. Although future long-term follow-up studies are still necessary to establish important key points regarding the best therapeutic protocol with such a new drug (such as the optimal time frame to keep the patient under treatment), denosumab promises to bring major changes to the current therapeutic paradigm for GCTs of the spine, which, up to now, has strongly relied on en bloc surgical resection.
authors.affiliation: Department of Neurosurgery - InvisionHealth Brain & Spine Center, Buffalo - NY, USA. Electronic address: tobiasmattei@yahoo.com.
authors.forename: Tobias A
authors.initials: TA
authors.lastname: Mattei
authors.affiliation: Department of Neurological Surgery, The Wexner Medical Center at The Ohio State University and The James Cancer Center, Columbus, OH, USA.
authors.forename: Edwin
authors.initials: E
authors.lastname: Ramos
authors.affiliation: The University of Illinois College of Medicine, Peoria, IL, USA.
authors.forename: Azeem A
authors.initials: AA
authors.lastname: Rehman
authors.affiliation: Department of Neurological Surgery, The Wexner Medical Center at The Ohio State University and The James Cancer Center, Columbus, OH, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Shaw
authors.affiliation: Department of Sarcoma Medical Oncology, MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Shreyasumar R
authors.initials: SR
authors.lastname: Patel
authors.affiliation: Department of Neurosurgery - InvisionHealth Brain & Spine Center, Buffalo - NY, USA; Department of Neurological Surgery, The Wexner Medical Center at The Ohio State University and The James Cancer Center, Columbus, OH, USA.
authors.forename: Ehud
authors.initials: E
authors.lastname: Mendel
mesh_terms: D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging; D000069448:Denosumab; D005260:Female; D018212:Giant Cell Tumor of Bone / Q000000981:diagnostic imaging / Q000188:drug therapy*; D006801:Humans; D011859:Radiography; D013125:Spinal Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D000069448:Denosumab
keywords: Denosumab; En bloc resection; Giant cell tumor; Osteogenesis; Osteolysis; Primary bone tumors; RANK ligand; Upper cervical spine