Spinal Metastatic Disease Survival Analysis of 146 Patients and Evaluation of 4 Different Preoperative Scoring Systems

Abstract

Study Design: This was a retrospective analysis. Objective: The objective of this study was to evaluate the predictive value of the 4 different scoring systems Tomita, Bauer modified, Tokuhashi revised, and Van der Linden and some parameters that are used in these scoring systems. Summary and Background Data: Prediction of the survival period before treatment for spinal metastasis is extremely important. A lot of scoring systems have been described to predict the survival periods and to select the ideal treatment modality in the literature. Materials and Methods: Retrospectively 146 patients with spinal metastasis were investigated between 2002 and 2011. The following parameters were analyzed: age, pathologic vertebra fracture, neurological deficit, visceral metastasis, diagnosis of primary tumor and its spinal metastasis interval, other skeletal metastasis, involved region of vertebra, and undergone spinal surgery. Patients were also scored by the 4 different scoring systems. The survival period was calculated from date of diagnosis of the spinal metastasis to the date of death or last follow-up (minimum: 12 mo). Cox regression, Kaplan-Meier survival test, and Cronbach alpha tests were performed for statistical analysis. Results: Median overall survival for all patients was 13 months (range: 1-68 mo). The primary tumor (P=0.015), existence of visceral metastasis (P=0.017), presence of pathologic vertebra fracture (P=0.009), and undergone spinal surgery (P=0.047) showed significant influence on survival. Each scoring system was reliable and concordant with the other scoring systems (Cronbach alpha=80%); however, after 2 years, Modified Bauer score appeared to be the most reliable system for predicting survival (Cronbach alpha=25%). Conclusions: According to this analysis, lung cancer, visceral metastasis, pathologic vertebra fracture, and undergone spinal surgery have shown a negative effect on survival. All 4 scoring systems were reliable for predicting survival of patients with spinal metastatic disease. However, modified Bauer scoring system seems to be more predictive after 2 years.