Management of spinal cord compression

Transcription

1 Management of spinal cord compression (SUMMARY) Main points a) On diagnosis, all patients should receive dexamethasone 10mg IV one dose, then 4mg every 6h. then switched to oral dose and tapered as tolerated b) Urgent treatment, within 24 hours of start of symptoms c) Interdisciplinary approach RADIATION THERAPY ONLY 1. Life expectancy of 3 months or less 2. More than one level of simultaneous SCC 3. Patients with paraplegia greater than 12 to 24 hours duration 4. Known radiosensitive tumor with no spinal instability or bony Impingement the spinal cord SURGERY FOLLOWED BY RADIATION (After interdisciplinary discussion with Neurosurgeon and Radiation Oncologist) 1. Pathological fracture with spinal instability or compression of the cord by bone 2. Unresponsive tumor with rapidly Progressive neurologic deficit TREATMENT OPTION: SURGERY ONLY (Possible indication (based on Neurosurgeon s evaluation) 1. Relapse at previously irradiated area 2. Progression during radiotherapy or failure to respond 3. No tissue diagnosis (when needle biopsy guided by computed tomography not possible CHEMOTHERAPY 1. Adjuvant treatment in adults with Chemo sensitive tumors 2. Initial or recurrent cord compression by a chemo sensitive tumor in a site of previous radiation or surgery ( FOR MORE DETAILS, SEE ENCLOSED TEXT )

2 2 MALIGNANT SPINAL CORD COMPRESSION Malignant spinal cord and nerve root compression is one of the main neurological complications of cancer. It ranks second to brain metastasis and it occurs up to 3% of all cancer patients. Anatomically, spinal cord compression (SCC) can be classified into intramedullary, leptomeningeal, and extradural compression. These guidelines will focus only on extradural compression. DEFINITION Epidural (extradural) spinal cord compression includes both clinical and radiological criteria compression of the dural sac and its contents (spinal cord and or cauda equina) by extradural mass, the minimum radiological evidence for cord compression is indentation of the theca at the level of clinical features. PATHOPHISIOLOGY Compression of the anterior aspect of the spinal cord or nerve roots is most common than the other sites. This results from the posterior extension of the vertebral body mass into the epidural space or from vertebral body collapse. Compression to less extent can also occur posteriorly via extension of the paraspinous tumor through a vertebral foramen as it occurs usually in lymphoma and testicular tumors. About 70% of cord compression involves thoracic spine, 10% cervical and 20% lumbosacral. It is important to remember that more than one site of compression may occur, and this is increasingly recognized with improved imaging techniques. CLINICAL FEATURES The earliest symptoms cord compression is back pain, sometimes with symptoms of root irritation, causing a girdle-like pain, often describes as band that tends to be worse on coughing or straining. Most patients have pain for weeks or months before they start to

3 3 detect weakness. In contrast to pain, the start of myopathy is usually rapid. Urinary symptoms such as hesitancy or incontinence and perianal numbness are later features. It is not uncommon for patient s weak legs to be attributed to general debility, and urinary bowl symptoms to be attributed to medications. Neurological signs and symptoms can vary from subtle to gross, from lower neurone to upper neurone lesion and from minor sensory changes to clearly demarcated sensory loss. Pre-treatment neurological status is the most powerful predictor of treatment outcome. Ambulation can be maintained to about 80% of patient who can walk at presentation. Once lost, motor function and sphinctric control is rarely restored. DIAGNOSTIC EVALUATION Clear indications of spinal cord compression demand emergent evaluation and multidiscipline consultation. When available, MRI is the preferable method of choice CT scan is superior to MRI for evaluating vertebral stability and bone destruction Plain films can be of help in detecting bony lesions of involved spine Occasionally, myelography followed by CT scan may be necessary if MRI not clearly identify a suspected tumor. TREATMENT Cord compression should be treated promptly, late cases with loss of ambulation and sphincter function is associated with poor prognosis and poor outcome. The goals of the treatment are (4Ps): Preservation or recovery of neurological function Palliation of pain Prevention of recurrence Preservation of spinal stability

4 4 - If treatment is started within 24 to 48 hours of onset of symptoms neurological damage may be reversible - Heightened awareness of the significance of back pain is the most important factor in successful treatment of cord compression CORTICOSTEROIDS Dexamethasone is the most frequently used steroid. Neither an optimal dose nor the best schedule has been defined. The dose of dexamethasone ranges from moderate (16mg in four times daily divided doses) to high 69mg /day. The steroids are usually tapered over 2 weeks. Recommendation: An initial 10 mg intravenous dexamethasone. The dose can be increased incrementally if no improvement is detected in the first 6 to 12 hours. After 2 days of stable intravenous dexamethasone, switch to 4 to 8mg every 6hours. Doses can be tapered every 4 days, if a neurological decline result from dose reduction, the dose is maintained at effective levels during radiotherapy until dose reduction is possible. A- SURGERY A number of different surgical techniques have been used to treat SCC. Historically, laminectomy alone was the intervention of choice. It fell out of fever because of high rate spinal instability and inferior ambulatory outcomes compared with radiotherapy alone. In most neurosurgical and orthopedic specialized centers, anterior decompression with mechanical stabilization has supplanted laminectomy as the principle surgical treatment of epidural metastasis arising from the vertebral body. However, even in selected patients, surgical excision of vertebral bodies necessitates a great surgical experience and yet carries considerable mortality, morbidity, and convalescence. Retrospective analysis has not shown advantage for patients managed by laminectomy and radiotherapy over radiotherapy alone. Therefore, surgical decompression is therefore now performed less routinely

5 5 INDICATION FOR SURGERY Tissue biopsy is needed when diagnosis is unknown Failure to respond to radiotherapy Spinal instability or bony compression of their spinal cord. by bone The level of cord compression is in an area previously irradiated(relapse post radiation or prior radiation to that area of spinal cord) B- RADIOTHERAPY Radiotherapy is routinely used in patients with epidural cord compression without spinal instability and bone compression. It reduces pain in approximately 70% of patients, improves motor function in 40 to 60%, and reverses paraplegia in as many as 10 to 15%. Patients who are ambulatory before treatment have an equivocal outcome with radiotherapy and surgery. The prescription of radiation given to treat malignant cord compression varies between centers. The administered dose ranged from 8 Gy in a single fraction to 40 Gy in 20 fractions over 4 weeks. INDICATION FOR PRIMARY RADIOTHERAPY For most situation Known radiosensitive tumors: lymphoma, m. myeloma, small-cell lung cancer, seminoma, neuroblastoma, or Ewing sarcoma with no spinal instability or compression of the cord with or without a rapidly progressing neurologic deficit C- CHEMOTHERAPY In adult patients, it is mainly utilized as an adjuvant treatment of tumors responsive to chemotherapy

6 6 References - Devita, textbook; cancer: principle and practice of oncology 5 th edition - ABC of palliative care emergencies; BMJ: 315(7121) : 1997 Dec 6 - Loblaw et al; Emergency treatment of malignant extradural spinal cord compression: an evidence based guidelines; JCO, 16(4): , 1998