Spinal hyperplastic bone marrow with a lumbar vertebral compression fracture mimicking vertebral metastasis.

A case of hyperplastic bone marrow that mimicked multiple bone metastases is presented in this report. A man in his 80s presented with lower back pain, and MRI revealed an L1 vertebral compression fracture and multiple signal changes in the whole spine that were low on T1 and high on fat-suppressed T2 images. Bone biopsies and imaging studies, including 18F-fluorodeoxyglucose positron emission tomography-CT, did not indicate primary or metastatic malignancy. On follow-up, MRI signal changes became unremarkable, and the patient showed no signs suggestive of malignancy. The final diagnosis was hyperplastic bone marrow and osteopenia with fragility fracture. Metastatic malignancy is commonly suspected in patients with a compression fracture and multiple vertebral lesions. However, clinicians should be aware that benign spinal hyperplastic bone marrow can have similar imaging findings to vertebral metastasis. Imaging, bone biopsy and careful follow-up are necessary to distinguish hyperplastic bone marrow from metastasis.