Revised: June 2014
Spinal tumours are divided into three general categories: (1) extradural, (2) intradural-extramedullary and (3) intradural-intramedullary (a true spinal cord tumour).
1) Extradural spinal tumours
These include metastatic lesions and primary bone tumours such as chordomas, osteomas, osteoblastomas, sarcomas, vertebral hemangiomas, and plasmacytoma/multiple myeloma and lymphomas.
The most common metastatic neoplasms to the spine include lymphoma, lung, breast and prostate cancer. Patients may present with localized spinal pain, which can progress to devastating neurologic deficits as the tumour advances to compress neural elements. Early diagnosis is thus paramount to minimizing often irreversible complications. Acute spinal cord compression is a medical emergency requiring urgent intervention. In general, the more severe the neurologic deficits (e.g. paralysis, loss of sphincter control) and the longer the duration of symptoms, the less likely the chances for recovery. For most patients with known primary cancer with clinical and imaging studies consistent with metastatic spinal disease, urgent radiation therapy is the primary treatment of choice. Surgical intervention is required in many instances, which include (1) spinal instability with or without neural compression, (2) failure to respond to radiation therapy (i.e. progression of neurologic deficits or persistent debilitating pain) or (3) unclear diagnosis requiring tissue sampling. Modern spinal surgical techniques can provide durable stability, local tumour control, resolution of severe pain and stabilization or improvement of neurologic deficits. A randomized clinical trial looking at modern surgical techniques and radiotherapy showed superior outcomes to radiation alone (1). As such, management requires a combined effort from the radiation oncologist and spinal surgeon.
2) Intradural-extramedullary tumours
Meningiomas and nerve sheath tumours constitute the majority of these lesions. These tumours can also extend outside the dural sleeve. Surgical resection remains the primary means of cure for these benign tumours. Radiation therapy is generally reserved for rare malignant cases or incomplete removals. Occasionally, seeding within the spinal subarachnoid space may take place from distal primary cerebral tumours, e.g. medulloblastomas, ependymomas, or lymphomas and metastatic carcinomas. These lesions are typically treated with spinal axis radiation. Intrathecal or systemic chemotherapy may also play a role.
3) Intramedullary tumours
The majority of true spinal cord tumours are astrocytomas or ependymomas. Other neoplastic lesions include hemangioblastomas, metastases, and frankly malignant astrocytomas. Ependymomas are generally amenable to surgical resection, often complete and curative. Astrocytomas tend to be less well marginated from normal spinal cord tissue, making complete removal difficult. Radiation therapy is generally accepted as the primary adjuvant to incomplete surgical removal of a spinal cord tumour.
References:
1. Patchell RA, Tibbs PA, Regine WF, et al. Direct decompressive surgical resection in the treatment of spinal cord compression caused by metastatic cancer: a randomised trial. Lancet 2005; 366:643.
