CASE 24
By: Dr. Sattam Lingawi and Dr. Alaa Al-Turkustani
HISTORY: Withheld.
What are your findings?
What is the differential diagnosis?
FINDINGS:
Fig 1: There is avid MDP osseous uptake noted at lower lumbar and sacral vertebrae.
Fig 2: Sagittal reconstructed CT demonstrates well defined lytic lesion in the anterior vertebral body of L4 surrounded by sclerotic rim (lytic/sclerotic) and diffuse increased bone marrow density with pathological L4 superior endplate vertebral body fracture and Grade I anterolisthesis of L4 over L5.
Fig 3, 4 & 5: Sagittal T1, STIR and post contrast T1 with fat saturation MRI demonstrating diffuse marrow conversion consistent with previous radiotherapy treatment involving all lumbar and sacral vertebrae. The same lesion is noted to be of low signal intensity on T1 and high signal intensity on T2 WI with strong enhancement post contrast administration. Partial collapse of the L4 vertebral body also noted. No intra-spinal extension or compromise seen.
DIFFERENTIAL DIAGNOSIS:
Metastatic bone lesion with pathological fracture.
Spondylodescitis.
DIAGNOSIS:
Breast cancer metastasis with post radiation changes and pathological fracture.
PEARLS AND DISCUSSION:
Spinal radiotherapy as a treatment for vertebral metastasis results in diffuse red - to - yellow bone marrow conversion. This is usually well demonstrated within 6 weeks after radiotherapy and persists ever since. Breast metastasis often appease as will defined sclerotic or mixed density destructive bone lesions. On MRI, malignant bone lesion demonstrates low T1 and high T2 signal intensities, reflecting oedema and bone marrow infiltration. Such vertebrae are weak and vulnerable to fracture with characteristic findings of posterior cortical bulging, para-vertebral soft tissue mass and intra-spinal/epidural extension of disease. Such finding is against benign (non-pathological) fractures.
Spondylodiscitis is in the deferential diagnosis however the infectious process usually starts in the disc and then involves the vertebral body.
FURTHER READING:
Lubdha M. Shah and Karen L. Salzman, Imaging of Spinal Metastatic Disease, Hindawi Publishing Corporation International Journal of Surgical Oncology Volume 2011, Article ID 769753, 12 pages doi:10.1155/2011/769753
Jin Kyeong Sung, MD, Won-Hee Jee, MD, Differentiation of acute Osteoporotic and Malignant Compression Fractures of the spine: Use of Additive Qualitative and Quantitative Axial Diffusion-weighted MR Imaging to Conventional MR Imaging at 3.0T
