Spine Tumours

Condition

There are many different tumours which can develop in the spine. ‘Tumour’ in medical terms means ‘swelling’ and is usually used to describe a growth. Some tumours are found incidentally and do not require any treatment, others can be very serious and fatal if not treated. The term tumour does not necessarily mean cancer as there are many benign tumours. In order to understand treatment options for tumours it is important to know about some terminology and principles. It will not be possible to discuss all tumours of the spine and the page focuses on the most common lesions. Management of any tumour, aggressive or not, should always be supervised by an oncologist or spine surgeon with a specialist interest in spinal tumours. In my practice, any tumour is discussed in a multidisciplinary team meeting (MDT). This team consists of spine surgeons, oncologists, radiologists and a pathologist to draw up the best possible management plan for the patient. This co-ordination is essential, as many patients will need more than one type of treatment, for example surgery followed by radiotherapy. The National Institute for Clinical Excellence in the UK (NICE) issued guidelines for the management of spinal metastasis. The MDT forms the central part.

Classifications of tumours

There are many different ways to classify tumours. Classifications are important in order to understand their origin, clinical and biological behaviour and treatment options.

Primary and secondary tumours

All tumours derive from a single cell which for reasons we often do not fully understand start to multiply. The normal control mechanisms for cell growths and multiplications do not work and the tumour starts growing. In principle, any tissue in the body can grow a tumour. A tumour which grows locally from a tissue in this area is called a primary tumour (for example a liver tumour in the liver or a brain tumour in the brain). Sometimes tumours can spread via the blood stream, lymphatic system or cerebrospinal fluid (in the brain and spine) and settle in different tissues or areas. This is called a secondary tumour or metastasis (for example a lung tumour which has spread from a bowel tumour). It is very important to know whether a tumour in the spine (or anywhere else in the body) is a primary or secondary tumour because it can significantly alter the management.

Benign and cancerous tumours

A benign tumour grows locally but usually does not spread to other parts of the body (there are very rare exceptions) and does not invade surrounding other tissues. It can, however, damage the surrounding tissue and organs by causing pressure. In the spine, a benign tumour can cause pressure on the spinal cord leading to gradual paralysis (myelopathy).

Cancerous tumours often destroy the surrounding tissues and can spread to other parts of the body. Destruction of the vertebral bodies in the spine can lead to collapse and instability.

Other classifications

Another classification commonly used for spinal tumours uses the relationship between the tumour and spinal cord. This classification does not take the nature of the tumour into account but is important for the understanding of surgical treatment.

Extradural tumours       

Intradural – extramedullary tumours These tumours lie within the sac containing the spinal cord (dura) but are outside the spinal cord itself. They most frequently arise from the sac or nerve roots within it. Examples are meningiomas or neurofibromas. The most common symptom is pressure on the spinal cord (myelopathy).

Intradural – intramedullary tumours 

 The tumour is located within the spinal cord. The most common symptom is myelopathy. In general, these are rare tumours. Examples are astrocytomas and ependymomas.

Making the diagnosis

There are important steps to make the correct diagnosis:

History    Important information comes from an accurate history of the patient’s symptoms and signs: duration and progression of symptoms, associated symptoms like weight loss, known other tumours or risk factors (for example smoking, which can cause a lung cancer that can spread to the spine)

Clinical examination     A thorough clinical examination is important to pick up signs of other involved organs in suspected metastatic disease and reveals the extent of the neurological deficit.

Investigations     Imaging the tumour and spine is an important step. Most tumours will require MRI scan and might need an additional CT scan or other x-rays. Some patients will require blood or urine tests. The only definite ways of making the diagnosis is taking a piece of tissue and analyze it (biopsy).

Sometimes, a biopsy is taken before any further treatment is planned. In cases where surgery is required anyway in order to deal with the complications (for example spinal cord compression) the tissue sample is taken at the time of the operation. In some cases, it might not be necessary to take a biopsy if the scan is very suggestive of a benign tumour which was found incidentally (for example a haemangioma). If a metastasis is suspected, patients will often undergo a series of test trying to find the primary tumour. An isotope bone scan can detect other metastases in the skeleton.