Accuracy of prognostic scores in decision making and predicting outcomes in metastatic spine disease.
INTRODUCTION: Management of metastatic spinal disease has changed significantly over the last few years. Different prognostic scores are used in clinical practice for predicting survival. The aim of this study was to assess the accuracy of prognostic scores and the role of delayed presentation in predicting the outcome in patients with metastatic spine disease. METHODS: Retrospectively, four years of data were collected (2007-2010). Medical records review included type of tumour, duration of symptoms, expected survival and functional status. The Karnofsky performance score was used for functional assessment. Modified Tokuhashi and Tomita scores were used for survival prediction. RESULTS: A total of 55 patients who underwent surgical stabilisation were reviewed. The mean age was 63 years (range: 32-87 years). The main primary sources of tumours included myeloma, breast cancer, lymphoma, lung cancer, renal cell cancer and prostate cancer. Of the cases studied, 29 patients had posterior instrumented stabilisation alone, 10 patients had an anterior procedure alone and 16 patients (with an expected survival of more than one year) had both anterior and posterior procedures performed. Twenty-three patients presented with spinal cord compression. The mean follow-up duration was 9 months (range: 1-39 months). Patients who were treated within one week of referral survived longer than anticipated. Patients were divided into three groups based on their expected survival. Actual survival was better in all three groups after surgery. Discrepancies in scores were prominent in patients with myeloma, breast and prostate cancers. Functional outcome was better in patients under 65 years of age. CONCLUSIONS: The prognostic scoring systems are not uniformly effective in all types of primary tumours. However, they are useful in decision making for surgical intervention, taking other factors into account, in particular the age of the patient, the type and stage of the primary tumour and general health.