Malignant spinal cord compression is a common problem in patients with advanced cancer.
About 1 in 5 patients with cord compression present with no prior history of cancer; most
Treatment of cord compression is based upon:
- The patient's performance status and prognosis (Patient factors)
- The degree of spine instability (Tumour factors)
- The availability of the different modalities of treatment (spinal surgery, radiotherapy, medical therapy) (Treatment factors)
Some patients present with cord compression during a terminal decline where disease control is non-existant. Subjecting them to surgery at this time, with no further hope of reversal of disease progression, is generally not warranted as they may not survive the procedure and are unlikely to derive long term benefit from it.
Spine stability can be judged using the SINS score, which is a combination of 6 factors predicting poor response to radiotherapy.
- Interfaces (Occiput-C2, C7-T2, T11-L1, L5-S1) = 3 points
- Mobile spine (C3-C6, L2-L4,)
- Semi-rigid (T3-T10)
- Rigid (sacrum below S1)
- Pain on movement:
- Pain on movement or relieved by lying flat = 3 points
- Pain not related to movement = 1 point
- No pain = 0
- Bone lesion type:
- Lytic = 2
- Mixed = 1
- Sclerotic = 0
- Spine alignment:
- Subluxation/translation = 2
- Kyphosis/lordosis = 1
- No deformity = 0
- Vertebral body involvement:
- > 50% collapse = 3
- < 50% collapse = 2
- No collapse but > 50% involved = 1
- < 50% involvement = 0
- Posterolateral extension:
- Bilateral = 3
- Unilateral = 1
- None = 0
The score is tallied up. A score of > 13 suggests spinal instability and surgical management should be instigated. A score of 7-12 is indeterminate but surgical advice should still be sought. Scores of 6 or less are thought to be stable (although if the patient develops worse pain on weight bearing then this is still of concern and should be reviewed by a surgeon regardless).
Treatment may be limited by the lack of availability of surgical or radiotherapy services. Spinal surgeons are difficult to find in regional Australia (even in smaller capital cities) and in some cases the decision to send someone for surgical treatment must also take into account the distance required for therapy and the patient's overall health. Radiotherapy is more widely available but many regional areas (eg. Dubbo, Shepparton, etc) are still > 100 km away from radiotherapy services.
General Approach to Treatment
Patients who are fit and well otherwise, with evidence of spine instability, should be treated with surgery and post-operative radiotherapy (typically 30 Gy in 10 fractions). This is the easy group! This is supported by a randomised trial which compared surgery + RT to RT alone, with significantly improved ambulatory rates (50% vs 90%) at the completion of treatment and longer duration of walking (mean 3 days vs 120 days with surgery).
Patients who have no spine instability are usually candidates for radiotherapy as it is better tolerated and safe when the spine is not about to collapse.
The difficult group are those with spine instability who have poor performance status. These patients should still receive radiotherapy despite an unstable spine as it is better than doing nothing.
The dose of radiotherapy varies from 8 Gy in 1# to 30 Gy in 10#, with most people using 20 Gy in 5 fractions. Shorter courses may be indicated for