An evaluation of spinal deformity in metastatic breast cancer.

Between October 1984 and January 1988 31 magnetic resonance (MR) imaging studies were performed on 27 patients with metastatic vertebral breast cancer (MVBC). The MR images were reviewed to determine the extent and type of sagittal spinal deformity, and whether spinal canal compromise was present. Adjunct studies were compared to determine the pathogenesis of spinal deformity and the etiology of spinal canal compromise. An analysis of the data revealed that a consistent pattern of sagittal spinal deformity exists with MVBC, and a classification system was developed to describe the stages of vertebral deformity. Criteria are suggested for identifying metastatic spinal instability. A protocol is presented for treating patients with metastatic spinal involvement. By understanding the natural history of metastatic spinal deformity, instability and spinal canal compromise can be recognized and treated early, before the onset of progressive deformity and neurologic sequelae.