General condition (Poor 0; Moderate 1; Good 2) Number of extra-spinal metastases (3 or more scores 0; 1 or 2 scores 1; 0 scores 2).

Number of spinal bony metastases (3 or more scores 0; 2 scores 1; 1 scores 2). Number of metastases to major internal organs (not removable 0; removable 1; no metastases 2).

Tissue of origin (lung, stomach 0; kidney, liver, uterus 1; other, breast, thyroid, prostate, rectum 2). Spinal cord palsy (complete 0; incomplete 1; none 2).

Tumour background knowledge

Overall, metastatic disease is the most common cause of spinal involvement and primary tumours of the spine are rare. Curative resection is possible in a few cases, but palliative intervention is more common. Pain from bony destruction and resultant mechanical instability may respond well to surgical stabilization.

Decompressive surgery may prevent (or prevent progression of) neurological impairment.

Epidemiology

Vertebral body lesions are more likely to be malignant and posterior lesions benign. Under the age of 21 most spinal tumours are benign, over 21 most are malignant. Under the age of 3 metastatic malignant tumours become more common again. Breast, lung, prostate, renal, thyroid and GI malignancies are the most common sources of primary disease.

Surgical treatment

Surgery is increasingly being performed. Following surgery, patients can often expect functional improvement, pain relief, and in a few cases cure. NICE has issued guidelines on the treatment of metastatic cord compression.² Decompression of compressed neural structures may lead to functional improvement even with prolonged paraplegia.

Simple laminectomy to ‘decompress’ the tumour is rarely indicated as the presence of the tumour (most frequently found in the vertebral body) is likely to lead to mechanical instability and thus kyphosis. Instrumented stabilization is frequently undertaken.

Surgical resection of tumour is aimed at improving survival. Resection may be undertaken anteriorly, or posteriorly, or both, and depending on the size and location of the lesion. In general terms, if a curative resection is hoped for, or survival is likely to extend beyond 6 months, intervertebral bony fusion should be undertaken to avoid instrumentation failure. If life expectancy is short and a palliative procedure is being considered, fusion may not be required and posterior surgery is more commonly undertaken.

Radiotherapy

	Mainly used to reduce tumour bulk. Many GI and renal tumours are resistant but most breast tumours are sensitive.
	Prostate and lymphoreticular tumours respond best.
	There is an increased risk of wound problems with adjuvant radiotherapy (separate radiotherapy and

surgery by a period of 6 weeks).

Minimally invasive surgery and cement vertebral body augmentation

These techniques are novel and their role is yet to be firmly established.

Some patients are too unwell or are unwilling to consider major surgery.

When pain caused by instability does not require decompression, vertebral body augmentation with high viscosity cement (PMMA) may be considered.

Minimally invasive surgery may allow the surgeon to stabilize the spine whilst minimizing soft tissue trauma facilitating a faster postoperative recovery in patients with limited life expectancy.

Specific tumours

Benign

Haemangioma – Slow growing and often asymptomatic. Often detected as an incidental finding on imaging.

Osteoid osteoma/osteoblastoma are usually found in the posterior neural arch. Most present with pain (NSAID sensitive). Excision is curative but NSAID may be all that is required.

Osteochondroma are most commonly found on the spinous process (related to the apophysis). Excision is for symptomatic treatment. Sarcomatous change has been described and excision is indicated if a large (> 10 mm) cartilage cap is seen on MRI.

Aneurysmal bone cysts typically affecting the posterior elements and giant cell tumours (affecting the vertebral body) are also seen.

Malignant

Myeloma/solitary plasmacytoma typically presents with pain and can be treated with radiotherapy (highly sensitive), or cement augmentation.

Chordoma is locally aggressive and may present with compression of pelvic contents.

Lymphoma most commonly occurs in the elderly ( meanage85)andmorefrequentlyinmenthanwomen.

Chondrosarcoma typically presents with pain and X-rays may show typical matrix calcification.

Osteosarcoma presents in the young (< 20). It is rare and survival is poor (median survival 6–10 months).

Intradural tumours

In contrast to extradural tumours most intradural tumours are not metastatic.

Extramedullary tumours occur inside the dura but outside the spinal cord. They are usually benign. They cause symptoms by compressing neural structures which can lead to pain or loss of motor function. Examples include neurofibromas, schwannoma ( of dorsal sensory roots) and meningioma.

Intramedullary tumours occur within the spinal cord. Most are malignant. Examples include astrocytomas (affecting children), ependymomas ( affecting adults), and rarely haemangiomas.

1. Tokuhashi Y, Matsuzaki H, Toriyama S, Kawano H, Ohsaka S. Scoring system for the preoperative evaluation of metastatic spine tumor prognosis. Spine 1990;15(11):1110–1113.

2. NICE Clinical Guideline 75. Metastatic Spinal Cord Compression. November 2008.