Metastatic spine tumors

Summary

Limited evidence from one moderate randomized controlled trial and three retrospective cohort studies suggests that survival, ability to walk, continence, and functional status may be improved and pain and complications reduced in patients experiencing metastatic spinal cord compression by adding surgical intervention to radiation therapy. A higher percentage of patients receiving combined surgery and radiation versus radiotherapy alone tended to be able to walk, and to walk longer, with statistical significance being reached in two of the three studies that examined this outcome. These potential benefits should be weighed against the costs, rigors of recovery from major surgery in patients whose health is already compromised, and life expectancy. In cohort studies, treatment choice based on patient presentation may bias (confounding by indication) results comparing treatments. A methodologically rigorous multicenter study is needed in order to confirm whether surgery followed by radiotherapy will improve outcomes for metastatic spinal cord compression patients.

Appendix references:

• 1 Frankel H L, Hancock D O, Hyslop G. et al . The value of postural reduction in the initial management of closed injuries of the spine with paraplegia and tetraplegia. I.  Paraplegia. 1969;  7 (3) 179-192
• 2 Maynard Jr F M, Bracken M B, Creasey G. et al . International standards for neurological and functional classification of spinal cord injury: American Spinal Injury Association.  Spinal Cord. 1997;  35 (5) 266-274

Clinical notes

Samuel Pantoja, Chile

With approximately 5 %, patients suffering from symptomatic spinal cord compression are a rather small subset of the cancer population. Their management is invariably demanding. The factors involved in treatment decision in these difficult cases are multiple. The authors focus on the capacity of decompressive surgery, as an addition to radiotherapy, in limiting neurological deterioration, a most feared situation for the treatment team, patients, and family.

It is common sense that in dealing with spinal cord compression from a metastatic tumor, surgical decompression has an opportunity to prevent or improve neurological compromise. It is the associated risks, morbidity, and cost involved in surgery that have made alternative, less aggressive treatment options to be considered.

An argument can be made for avoiding sometimes extensive surgery in patients with spinal metastases but no cord compression by treating the lesion with radiation. If, however, cord compression is evident and radiotherapy is elected as treatment, not only will the results be very significantly poorer but, should the patient later require surgery, his / her complication rate from wound breakdown will be much higher, in the 40% area. One must also keep in mind – and advert patients and family – that, should the patient remain or become paraplegic, the drama will not end there, but will include, in addition to mobility impairment, the complications associated with prostration.

A common situation is, where, in the presence of cord compression with mild neurology, patients are offered radiotherapy with the option of later surgery as required by symptoms. Again, if this is the chosen treatment, it must be clear to everybody that there is a probability of failure with a need for emergency decompression with the addition of a three-fold chance of significant local complications.

Surgery is, no doubt, an additional aggression for these frequently debilitated patients. There is rarely an opportunity for extensive preoperative evaluation, and this may further increase risks. Clearly, radiation of spinal metastases with no cord compression (a majority) remains the predominant and logical treatment.

Nevertheless, as the analyzed publications strongly indicate, the probability for surgical decompression followed by radiotherapy to maintain or recover neurological function in the presence of cord compression significantly exceeds that of radiotherapy alone, and it should be made available to all but the more debilitated subjects in this difficult situation.

Clinical notes

Marcelo Valacco, Argentina

The so-called spinal cord compression caused by epidural spinal metastases is a neurological complication from which about 5% of patients who have a tumor disease suffer. The authors of these studies agree that the expectation of survival from diagnosis is 3 – 6 months on average. Both the nature of the primary tumor and the neurological compromise are the most important factors that affect survival.

Radiotherapy is highly recommended in most cases since it has the effect of preventing larger tumor growth and neurological damage, as well as reducing pain.

The analysis of the studies shows that the best results are obtained when patients are treated with surgery followed by radiotherapy because the surgical decompression is immediate, while it takes several days for radiotherapy alone to have the desired effect. Decompressive laminectomy was traditionally used as primary surgical management. However, the indiscriminate use of this technique resulted in poor performance and high complication rates. Therefore, there is a clear trend to make use of instrumentation after the tumor decompression.

Such studies are Class of evidence (CoE) II and III. Those of CoE I would strengthen the scientific aspect of the findings, yet it is difficult to establish treatment protocols when patients in fact show a severe neurological compromise.

In the Italian Hospital of Buenos Aires, general practicers, oncologists, psychotherapists, and physiatrists work together in a multidisciplinary way when dealing with these patients. The aim of this method is to provide them with the most appropriate treatment according to the expectation of survival. Every patient with these characteristics is a real challenge and on many occasions the different treatment alternatives to deal with the case become a topic to be discussed in seminars together with other professionals. It is, therefore, extremely useful to set scores and prediction scales in order to establish treatment guidelines.

In conclusion, the epidural spinal compressions caused by spinal epidural metastasis happen to be rather complex. Each case should be analyzed taking into account the expectation of survival of the patient, the type of tumor, the degree of neurological compromise, the degree of metastasis known and its location, the response to treatments, the general state of the patient, and the patient's consent to undergo different therapeutic treatments.

Possible treatments involve steroids, radiotherapy, surgery, chemotherapy, and hormonal therapy. In case of severe neurological compromise, the use of dexamethasone at variable doses is highly recommended. Radiotherapy is suggested in case of sensitive tumors, and surgery followed by radiotherapy applies to patients whose tumors are less sensitive to radiotherapy, who have an incomplete neurological compromise or mechanical instability, and an expectation of survival of more than 3 months.