Radiosurgical Decompression of Malignant Epidural Spinal Cord Compression

1
Radiosurgical Decompression of Malignant
Epidural Spinal Cord Compression
Samuel Ryu, M.D., Jack Rock, M.D., Rajan Jain,
M.D., Shehanaz Ellika, M.D., Jian-Yue Jin, Ph.D.,
Joseph Anderson, M.D., Benjamin Movsas,
M.D.Radiation Oncology, Medical Oncology,
Neurosurgery, Neuroradiology, Henry Ford
Hospital, Detroit, Michigan
Radiographic Tumor Response
Background
Radiosurgery Technique
Complete response 27 80 response 14 50-79
response 16 lt 50 response 23 Stable 14 P
rogressive 6

• Spine radiosurgery has demonstrated the accuracy
  and clinical effectiveness.
• Feasibility Study
• Precision was within 1.36 ? 0.11 mm.
• Rapid dose fall-off from 90 to 50 isodose
  lines was 5.24 ? 0.92 mm.
• Efficacy Study for spine metastasis
• Rapid pain relief
• Median time to pain relief 14 days
• (as early as 8 hrs)
• Durable Pain relief
• Median duration of pain relief 13 months
• Partial volume spinal cord tolerance
• 10 Gy to the 10 volume of the spinal cord,
  defined as 6 mm above and below the target.

Epidural decompression in 80

• Radiosurgery dose Single dose 14-20 Gy
  prescribed to the 90 isodose line
• Spinal cord dose constraint 10 Gy to the 10
  volume of the spinal cord
• Immobilization - Bodyfix with vacuum support
• Equipment BrainLab Novalis
• Image-guided Positioning
• Planning 7-10 Intensity modulated beams with 3mm
  microMLC, directed from posterior

Breast cancer with circumferential epidural
compression. This was treated with radiosurgery
16 Gy. After 2 months, there was a near-complete
tumor response and thecal sac decompression
Neurological Improvement
Purpose
Neuro status before radiosurgery Neuro Respons
e Intact Deficit Intact 86 61 Improved
- 10 81 Stable - 10 Progressed 14
19
Since radiosurgery has a rapid dose fall-off, it
can be used to treat epidural spinal cord
compression. Spine radiosurgery can deliver a
high radiation dose to the epidural tumor and
minimize the radiation to the adjacent spinal
cord. Therefore, phase II study was performed to
determine the efficacy of radiosurgery for
malignant epidural spinal cord compression.
Thecal Sac Decompression

• Thecal sac decompression was achieved in in 80.
• Average epidural tumor volume reduction was
• 68 ? 32.
• Thacal sac patency improved from 55?3 to 77?3 .
  (plt0.001)

Summary
Methods

• Radiosurgery achieves significant tumor response
  and decompressive effect of spinal cord
  compression.
• Thecal sac decompression was achieved in 80 of
  patients with average 68 tumor volume
  reduction.
• Neurological status was improved or stable in
  81 of patients who had deficit, and stable in
  86 of patient who had no deficit.
• Spine radiosurgery can be a viable treatment
  option for spinal cord compression. Even minimal
  tumor response relieves the spinal cord
  compression and potential neurologic
  improvement.

• Total 67 patients with 93 lesions of epidural
  spinal cord compression at the solitary spine
  level were accrued. All patients had
  pathology-proven malignancy and had epidural
  tumor seen on MRI or CT scan.
• Median followup time was 8 months (2-30 months).
  Followup included neurological exam and imaging
  studies every 2 months.
• Endpoints were 1) radiographic tumor contol, 2)
  neurological improvement, and 3) thecal sac
  decompression.