Re-irradiation of vertebral bodies

Abstract

Improvements in clinical care and therapy mean that more patients are diagnosed and living longer with vertebral metastases. Thus, they are at risk of the development of recurrence that requires re-irradiation. Normal tissues often recover some of the damage caused by the primary radiotherapy with time and specific normal tissues can tolerate a considerable retreatment radiation dose. However, the risk of normal tissue damage and the impact on the quality of life must be considered and should be done with maximum care and accuracy especially in the vertebral area. For many years conventional external beam radiation therapy was the standard treatment modality. Fortunately, with crucial technological progress in the field of radiation oncology we are able to integrate body imaging with accurate treatment delivery methods as stereotactic body radiotherapy to improve the efficacy, shorten the overall treatment time and potentially reduce treatment-related toxicities. A short description of re-irradiation strategy covering diagnostic procedures, volume delineation, dose reconstructions, treatment planning, and guidelines are outlined. Moreover, publications on vertebral bodies re-irradiation summarizing available knowledge about toxicity, dose-volume constraints, local control, and pain response are followed. Although the knowledge is limited to a series of a single institution, it shows that re-irradiation is an effective treatment for local control and pain response. Furthermore, treatment was also shown to be safe with low risk of spinal cord damage which is one of the most worrisome toxicity.

Keywords: Complications; Radiotherapy; Re-irradiation; Tissue tolerance; Vertebral body.