Spinal tumours

How common are spinal tumours?

Primary non-lymphoproliferative tumours of the spine are uncommon and make up less than 5% of bone neoplasms. Metastatic disease of the spine is much more common.¹

Approximately 40-80% of patients who die from cancer have bony metastases at the time of death, with the spine being the most common metastatic skeletal location. Problems can be caused by direct compression on the spinal cord, vascular obstruction and invasive infiltration.

In children, the common benign tumours include osteoid osteomas and osteoblastoma.

Primary spinal tumours

See also the separate Bone Tumours, Myeloma and Non-Hodgkin's Lymphoma articles.

Bone-producing tumours of the spine

See also the article on Bone Tumours

These include:

• Osteoid osteoma - benign and locally self-limiting:
  

  • Typically presenting in children aged 10-20 years - mostly males.

  • They involve the axial skeleton about 10% of the time.

  • Over half of osteoid osteomas are found in the lumbar region; the next most common site is the cervical region, then the thoracic region and then the least common site - the sacral region.

  • Osteoid osteomas are usually symptomatic.

  • They can result in painful scoliosis, muscular atrophy, radicular pain and gait disturbances secondary to pain and splinting.

• Osteoblastoma - benign but expand locally and are aggressive:
  

  • They occur in young patients in the second or third decade of life.

  • They are twice as common in males as they are in females.

  • Patients typically complain of dull localised pain and paraesthesiae.

  • There may be paraparesis and, if the tumour is large enough, paralysis.

• Giant cell tumours - most are benign:
  

  • Malignancy occurs in only a small minority of cases and is usually related to previous irradiation in the area of the tumour.

  • These are more common in women and occur in the third to fifth decades of life.

  • They can increase dramatically in size during pregnancy, secondary to hormonal influences.

  • The symptoms include pain with radicular pattern and neurological impingement with weakness and sensory deficits.

• Osteosarcoma - a malignant spindle cell lesion which produces osteoid, the organic portion of the bone matrix, secreted by osteoblasts:
  

  • Osteosarcomas of the spine are rare.

  • They typically present in patients in the fourth decade of life and have a male predominance.

  • Osteosarcomas are most common in the lumbosacral segments.

  • Patients often present with pain and a palpable mass.

  • Neurological symptoms are found in the majority of patients.

  • Serum alkaline phosphatase may be elevated.

Cartilage-producing tumours of the spine

• Osteochondroma - they also are commonly referred to as exostosis:
  

  • It is a benign lesion with cartilaginous cap.

  • Osteochondromas make up 4% of all solitary spine tumours.

  • They occur in patients aged 20-30 years.

  • They are more common in males.

  • Osteochondromas are more common in the cervical spine.

• Chondrosarcoma - malignant cartilage-producing tumours:
  

  • Chondrosarcoma is the second most common non-lymphoproliferative tumour of the spine.

  • Chondrosarcomas comprise about 10% of all spinal tumours.

  • Men are affected more often than women.

  • The mean age at presentation is about 45 years.

  • The thoracic spine is the most common site.

  • The most common symptoms are pain, a palpable mass and neurological complaints.

Spinal cord tumours²

• Can occur in the parenchyma of the cord (intramedullary lesions), in the thecal sac but external to the cord (extramedullary lesions), or outside of the thecal sac (extradural lesions).

• Intramedullary spinal cord tumours in adult patients account for only 5–10% of all spinal tumours, but are the most common spinal tumour in children.7 Astrocytomas, ependymomas and haemangioblastomas comprise the majority of adult intra-medullary lesions.

• Intradural extramedullary spinal cord lesions include meningiomas, neurofibromas and schwannomas.

Lymphoproliferative tumours

• Multiple myeloma and plasmacytoma - multiple myeloma is the most common primary malignancy of bone and the spine:
  

  • Multiple myeloma is a systemic disease that affects middle-aged people and is characterised by areas of local bone destruction.

  • The underlying cell line is the malignant plasma cell, which produces abnormal quantities of immunoglobulins.

  • Patients complain of pain that may be worse at night.

• Lymphoma - this is associated with a large infiltrate of lymphoid cells.

Tumour of notochordal origin

• Chordoma - rare (incidence 0.08 in 100,000 individuals) low-grade notochordal tumour of the skull base, mobile spine and sacrum which behaves malignantly and has a poor prognosis despite indolent growth patterns.³
  

  • Often present late in the disease course, tend to encapsulate adjacent neurovascular structures, seed resection cavities, recur locally and respond poorly to traditional radiotherapy and conventional chemotherapy, all of which make chordomas challenging to treat.

  • Extent of surgical resection and adequacy of surgical margins are the most important prognostic factors.

  • Although chordoma has been traditionally considered resistant to conventional radiotherapy and chemotherapy, advances in radiation targeting and treatment schemes have enabled high doses of radiation to the tumour itself while minimising radiation toxicity to surrounding structures.

Round cell tumour

• Ewing's sarcoma - Ewing's sarcoma is the most common non-lymphoproliferative primary malignant tumour of the spine in children:
  

  • Patients with Ewing's sarcoma usually present aged 10-20 years.

  • The most common site of occurrence in the spine is the sacrococcygeal region.

Metastatic tumours

Approximately 30% of patients with cancer develop symptomatic spinal metastases during the course of their illness. Up to 90% of cancer patients have metastatic lesions within the spine at the time of death.⁴ The most common tumours that metastasise to the spine are as follows:

• Prostate cancer.

• Breast cancer.

• Lung cancer.

• Renal cancer.

• Gastric cancer.

Signs and symptoms of spinal tumours (presentation)

Symptoms

• Systemic or constitutional symptoms tend to be more common with malignant or metastatic disease than in benign lesions.

• Symptoms usually develop slowly.

• Back pain is the most frequent symptom for patients with either benign or malignant neoplasms of the spine:
  

  • With extradural lesions pain is typically aggravated by coughing or straining.

  • It may be radicular, localised to the back or felt generally in an extremity.

• Neurological deficits secondary to compression of the spinal cord or nerve roots also can be part of the presentation:
  

  • The degree of neurological compromise can vary from slight weakness or an abnormal reflex to complete paraplegia, depending on the degree of encroachment.

  • The loss of bowel or bladder continence can occur from neurological compression or can be secondary to a local mass effect from a tumour in the sacrococcygeal region of the spine, as occurs in chordomas.

  • There may also be motor deficits, paraesthesia, numbness in legs and loss of sphincter control.

Signs

See also separate Examination of the Spine article.

• Local spinal tenderness.

• Motor deficits.

• Sensory changes.

Factors suggesting spinal metastases include:⁵

• Cancer:

  • Past or current diagnosis of cancer.

  • Suspected diagnosis of cancer.

• Pain characteristics suggesting spinal metastases:

  • Severe unremitting back pain.

  • Progressive back pain.

  • Back pain aggravated by straining (eg, coughing, sneezing or bowel movements).

  • Night-time back pain disturbing sleep.

  • Localised tenderness.

  • Claudication (muscle pain or cramping in the legs when walking or exercising).

Diagnosing spinal tumours (investigations)

• FBC and differential white cell count should be taken.

• Renal function and electrolytes should also be requested.

• ESR, or CRP to help to distinguish between neoplastic and infectious processes.

• Elevations in serum calcium or alkaline phosphatase also can provide evidence for neoplastic bone processes. Specific studies such as serum electrophoresis or urine electrophoresis also can be performed to evaluate the likelihood of multiple myeloma or plasmacytoma.

• Plain X-ray, CT scan or MRI scan should be requested.

• Myelography may also be useful.

Confirmation of diagnosis and ascertaining the specific tumour type is by biopsy of the spine lesion after all radiographic studies have been completed.⁶ Biopsy can be performed with open or by percutaneous image-guided technique. Percutaneous needle biopsies may not supply adequate tissue for the diagnosis of a primary tumour of the spine.

Treatment and management of spinal tumours

Decompression and excision where possible. Minimally-invasive spinal procedures and minimal access surgical techniques have facilitated quicker patient recovery and return to systemic treatment. These interventions help to alleviate pain and improve quality of life, even in patients with a relatively short life expectancy. Radiotherapy may be considered in non-surgical candidates or as adjuvant therapy for improving local tumour control. Stereotactic radiosurgery has facilitated this even in radioresistant tumours and may even replace surgery in radiosensitive malignancies.⁷

Intraoperative radiotherapy (IORT), in which surgery and radiotherapy are performed in the same session, has shown benefits with pain relief and neurological improvement, as well as benefits with local tumour control and radiation-induced toxicities. However, short follow-ups and the absence of randomised trials indicates the need for further research to confirm the outcomes of IORT in spinal tumours.⁸

For people with spinal metastases without metastatic spinal cord compression who have non-mechanical spinal pain:⁵

• Offer 8 Gy single fraction radiotherapy, even if they are paralysed, or

• Consider stereotactic ablative body radiotherapy for people with a good overall prognosis or oligometastases (up to 3 discrete metastases anywhere in the body) with spinal involvement.

• Radiotherapy for haematological malignancy with spinal metastases may reduce the success of stem cell harvest. If stem cell harvest is being considered, the use of radiotherapy should be discussed with the relevant haematology multidisciplinary team.

Surgical resection combined with radiotherapy is the treatment of choice for most patients with spinal cord tumours, as no significant improvement in survival has been observed with chemotherapy alone.²

See also the separate articles on Bone Tumours and Myeloma further information.

Complications of spinal tumours

Complications associated with spinal tumours can be divided into the following:

• Complications associated with the tumour, its recurrences or its metastases:
  

  • Neurological complications include radicular pain or focal weakness from impingement on a nerve root and complete or incomplete paraplegia from direct pressure on the spinal cord. See also separate Spinal Cord Injury and Compression article.

• Complications associated with the surgical, radiation or chemotherapeutic treatment of the tumours:
  

  • Complications that result from the treatment modality employed may be related to structures sacrificed during the surgical resection to obtain clear margins, structures in the path of radiation therapy or the systemic effects of chemotherapy.