Benign giant cell tumor of the spine: an unusual indication for radiotherapy.

INTRODUCTION: Giant cell tumors are rare primary bone tumors. Multicentricity as well as spinal localization is extremely rare. CASE REPORT: We report about a 64-year-old female patient presenting with history of three osseous and one pulmonal manifestation of a benign giant cell tumor that have manifested metachronously within 23 years. The two periphery bone and the one pulmonal manifestation were treated surgically with success. Now, a further osseous lesion occurred at the seventh vertebra of the thoracic spine and was treated by dorsal instrumentation and replacement of the seventh vertebra. Nine months later, local recurrence of this benign giant cell tumor developed at the thoracic spine and was treated with radiotherapy with a total dose of 45 Gy. Three months after salvage radiotherapy definite local progress occurred localized within the former radiation treatment field. Due to neurological deficits a laminectomy and a stabilization of the destroyed sixth vertebra with bone cement was carried out. Histopathological examination again showed benign giant cell tumor without suspicion of malignancy.
CONCLUSION: In the literature the use of radiation therapy remains an appropriate therapy option in benign giant cell tumors with minimal adverse sequelae if primary surgical treatment is not feasible or fails. In cases of definitive radiotherapy a total dose > 45 Gy should be discussed.