Magnetic resonance imaging diagnoses of bone scan abnormalities in breast cancer patients

To investigate the type of MR imaging diagnosis that corresponded to spinal lesions detected on a bone scan according to the number of lesions in breast cancer patients.

We retrospectively reviewed spinal MR images of 134 patients with breast cancer whose bone scans showed one or more spinal hot uptakes. The patients were grouped according to the number of spinal lesions detected on the bone scan: one or two lesions versus multiple (more than two) lesions. By using MR imaging, we determined the etiology of the spinal lesions in terms of being either benign or malignant. If the lesions were benign, we further categorized them into several specific pathologies.

Sixty-four (48%) of 134 patients had one or two spinal lesions as seen on a bone scan. On MR imaging, 45 (70%) of the 64 lesions had benign pathologies, whereas 19 lesions (30%) were malignant. The benign pathologies in the 45 patients included facet arthrosis in 20 patients (44%), discovertebral degeneration in 12 patients (27%), compression fractures in eight patients (18%), and Schmorl's nodes in five patients (11%). Seventy (52%) of 134 patients had multiple spinal lesions as seen on the bone scan, and MR imaging revealed multiple bone metastases in 67 patients (96%) and facet arthrosis in three patients (4%).

One or two spinal lesions seen on a bone scan in breast cancer patients are more likely to be benign pathologies such as facet arthrosis, discovertebral degeneration, compression fracture or Schmorl's node on MR imaging.