SPINAL CORD COMPRESSION

SPINAL CORD COMPRESSION Oncologic emergency Occurs in 5% of patients in autopsy series In 20% of patients with neoplastic involvement of the vertebral column Usually occurs in the setting of disseminated cancer May be the initial manifestation of malignant disease or the sole site of disease recurrence Requires emergency diagnostic procedures and treatment to prevent irrevercible neurologic injury.

TUMOR TYPES that may cause compression Breast 21% Lung 17% Lymphoma 9% Prostate 7% Sarcoma Myeloma 6% Kidney Other 27%

PATHOPHYSIOLOGY Vertebral body – most commonly involved (-> pedicules ->posterior lamina) ->> collapse of the vertebral body or erosion of cortical bone and tumor invasion into the extradural space Far less commonly – tumor extension from a paravertebral mass through the intervertebral foramina into the spinal canal Intramedullary metastases – extremely rare Pathologic consequences: from reversible vasogenic edema to irreversible necrosis The part of he vertebra most commonly involved is the vertebral body, followed by the pedicules and posterior lamina. Metastasis to bone often results in eventual collapse of the vertebral body or erosion of cortical bone and tumor invasion into the extradural space. Far less commonly tumor may extend from… Pathologic consequences may vary from…

LOCATION 70% - thoracic 20% - lumbar 10% - cervical 9-30% - multiple sites! 70% of cord compressions are thoracic in origin, 20% are lumbar, 10% are cervical and 9-30% are multiple.

CLINICAL MANIFESTATION back pain-initial symptom in 70-95% of adults and 80% of children almost always precedes diagnosis by several days to many months local or radicular *local - in almost all cases; close to the site of compression; usually constant, dull, aching, worse when the patient is supine; exacerbated by movement, sneezing or neck flexion *radicular – often intermittent and shooting; in the cervical or lumbar lesion may involve the shoulder or limb * spinal percussion enables to establish the level of lesion *the opposite to degenerative joint disease or herniated disc

CLINICAL MANIFESTATION Weakness – in approximately 80% of patients Usually follows pain by week or months Most evident when affects proximal muscles of the lower extremity (difficulty in climbing stairs or rising from chair) May evolve to paraplegia within hours or days High cervical cord lesions are potentially fatal – may produce paralysis of respiratory muscles and the diaphragm * Neurologic deficits tend to manifest in the lower extremities – preponderance of thoracic and lumbar spine lesions

CLINICAL MANIFESTATION Sensory disability (sensory loss, paresthesia) *patients generally demonstrate more motor than sensory disability (most common anterior compression) Autonomic dysfunction (urinary frequency, urgency, urinary retention, constipation, impotence) – occurs late, associated with a poor prognosis Because the vertebral body is usually involved, anterior compression of spinal cord is most common and patients generally demonstrate more motor disability than sensory disability.

DIAGNOSTIC PROCEDURES Plain radiographs - destruction of the cortical bone of the pedicles - collapse of the vertebral body - erosion of lamina - identification of a paravertebral soft tissue mass Detect bony abnormalities in 72% of patients with epidural cord compression May be normal in 60% of patients with compression by lymphoma or pediatric malignancies! ! In these cases, posterior or posterolateral compression results from paraspinous soft tissue mass invading the vertebral foramen – these lesiones are detected more reliably with CT or MRI

DIAGNOSTIC PROCEDURES Myelography – historical method - provides only indirect evidence of extradural disease - impaired flow of contrast medium injected into the subarachnoid space by lumbar puncture due to extradural tumor manifests as a block on plain radiographs - does not detect multiple sites of lesions

DIAGNOSTIC PROCEDURES MRI - imaging modality of choice! - assesses full length of the spinal cord (multiple sites of compression) - better in delineation of paraspinous soft tissues - detects vertebral foramina invasion - safer, more convenient, better tolerated - use of contrast (gadolinium) demonstrates intramedullary metastases, leptomeningeal involvement, paravertebral masses Provided that it is available and there are no contraindications for it. - extremely useful in planning radiotherapy or surgery

TREATMENT * Patients diagnosed with spinal cord compression should be treated emergently! * Treatment decision depends on: - patient’s expected survival - location and mechanism of compression - rapidity of neurologic progression - tumor histology - extent of spinal involvement - previous treatment method (rth) Corticosteroids Radiotherapy Surgery Chemotherapy

TREATMENT Goals of treatment: preservation or recovery of neurologic function palliation of pain prevention of local recurrence preservation of spinal stability

TREATMENT Corticosteroids (dexamethasone) - improve the initial rate of neurologic recovery - lead to stabilization of neurologic deficits before the start of definitive treatment - administered throughout an entire course of radiotherapy - initial dose of 10-100mg intravenously followed by oral daily dose of 4-24mg every 6 hours When the diagnosis of epidural compression has been made, dexamethasone should be administered.

TREATMENT Radiotherapy - definitive treatment for most patients (except of patients with compression from retropulsed bone, spinal instability, patients without a clinical or pathologic diagnosis of cancer – considered for surgery; children with chemosensitive tumors) - reduces pain in 70% of patients - improves motor function in 45-60% of patients Children with chemosensitive tumors should be considered for initial chemotherapy. Immidiate surgical decompression should be cosidered for patients with neurologic progression during radiotherapy. Patients previously treated with rth?

TREATMENT Surgery - laminectomy – for posterior or posterolateral tumors - vertebral body resection – for anterior tumors - spinal stabilization

TREATMENT Chemotherapy - pediatric patients with chemoresponsive tumors - adjuvant treatment in adults with chemosensitive tumors - initial or recurrent cord compression by a chemosensitive tumor in a site of previous radiation or surgery

CONCLUSIONS * As the median age of the population increases and cancer survival is prolonged by more effective treatment, spinal cord compression will remain an important oncologic problem. * Early intervention is essential for successful treatment.