The role of denosumab in the complex treatment of giant cell tumor of the spine: reducing of local recurrence rate, surgery time and blood loss

Objective. To assess the effect of the combined treatment method including preoperative denosumab therapy on the results of treatment of patients with giant cell tumors of the spine.Material and Methods. A single-center retrospective-prospective study of a series of clinical cases included 15 patients with giant cell tumors of vertebrae. The average follow-up period was 56 months. A total of 11 patients received denosumab therapy according to the following scheme: 120 mg subcutaneously on the 1st, 8th, 15th and 28th days of the first month and then once every 28 days. Surgical options included marginal resection, segmental resection, or en-bloc resection with or without spinal reconstruction/stabilization. In the case of locally advanced and inoperable disease, long-term therapy with denosumab was carried out until the disease progressed or serious adverse events appeared.Results. Thoracic vertebrae were involved in 7 (46.6 %) of 15 cases, lumbar in 4 (26.7 %) and cervical in 4 (26.7 %). Local recurrence rate after surgery alone was 40 % (2/5), average time to recurrence onset was 4.5 months. No relapses were observed after combined treatment performed in four patients. Disease progression during long-term denosumab therapy for inoperable disease recurrence was not recorded (0/7). The average number of denosumab injections before surgery and during long-term therapy was 15 and 24 injections, respectively. Denosumab therapy allows reducing the duration of surgery and the volume of blood loss.Conclusion. Combined therapy of giant cell vertebral tumor allows to reduce the risk of recurrence of the disease, as well as to reduce surgery duration and blood loss. Long-term continuous therapy for inoperable cases allows achieving long-term stabilization of the effect. Due to the rarity of giant cell tumors of the spine, a further prospective recruitment of patients is required to study the efficacy and safety of combined therapies.