Neoadjuvant denosumab for the treatment of resectable giant cell tumor of bone: First results of Russian multicenter study.

11521Background: Giant cell tumor of bone (GCT) is a relatively rare, benign but locally aggressive osteolytic skeletal neoplasm of young adults. This study is non-interventional observational GCT treatment study in the Russian Federation (RF). Designed to detect epidemiology data as well as the clinical efficiency of surgical and/or denosumab (Db) treatment of GCT in the RF. Methods: Between August 2016 and October 2017, 112 adult patients (pts) with GCT were enrolled. Ten Russian Cancer Center are included in this study. The primary endpoint was Time-To-Progression (TTP). Adult and skeletally mature adolescent pts with resectable and unresectable GCT (N = 54) received subcutaneous Db 120 mg every 4 weeks with a loading dose of 120 mg SC on study days 8 and 15. Options for surgical treatment (N = 25) include intralesional curettage (InC) (alone or followed by filling of the defect with bone cement), marginal excision (MEx), a wide local excision, or en bloc resection with or without reconstructive surger...