Page 21 - Predicting survival in patients with spinal bone metastasesL

INTRODUCTION
Spinal bone metastases (SBM) are a frequently observed complication of malignant disease. Due to an increase in the survival times of patients with malignancies, the incidence of SBM is expected to rise over the years.1,2 The majority of symptomatic SBM are caused by breast, prostate and lung cancer (56-74%)3,4,5 and most commonly arise from the thoracic part of the spine (51-67%).4,6 Patients present with pain due to destruction of bone tissue and/or and neurologic complaints due to nerve root and/or spinal cord compression.7,8 Both radiotherapeutical and surgical interventions are effective in treating these symptoms. However, due to the relatively short life expectancy of these patients, overtreatment is a common problem. Therefore, an accurate estimation of survival plays a pivotal role in selecting the appropriate treatment. Survival estimation by clinicians has been shown to be too optimistic9 and to provide an aid for this difficult task, several prediction models have been developed.4,8,10,11 These models employ different sets of prognostic factors such as performance score, primary tumor and the presence of visceral metastases to stratify patients with SBM according to survival risk, enabling clinicians to select a more appropriate treatment. Several studies have been undertaken to assess the prognostic value of these models and the factors being used.12,13 The aim of this systematic review was to identify prognostic factors that are associated with survival in patients with spinal bone metastases in order to help guide development of predictive models.
METHODS
Search strategy
The review protocol for this study was prospectively registered online at PROSPERO under registration number CRD42014006706 (www.crd.york.ac.uk/prospero). The search strategy was formulated in collaboration with a medical librarian to focus on the key terms survival, prognostic factors and spinal bone metastases, or variations thereof. The electronic databases Medline, Embase, Web of Science, Cochrane and Cinahl were searched from January 1999 up to September 2014. The complete search strategy is available as an online supplement.
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SYSTEMATIC REVIEW
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