Evaluation of the Scoring System in Patients with Spinal Metastases from Nasopharyngeal Carcinoma

Background The decision of operative treatment of patients with spinal metastases is dependent on the patient's predicted survival. The Tokuhashi, Tomita, Bauer, and Oswestry scores have been devised for survival prediction; however, none of these systems have been evaluated in nasopharyngeal carcinoma (NPC). We aimed to identify prognostic factors for survival, and investigate the predictive value of these scoring systems in predicting survival of the patients with spinal metastases from NPC. Methods We retrospectively evaluated the patients treated at our institution for spinal metastases from NPC. The predicted survival according to the four scoring systems (Tokuhashi, Tomita, Bauer, and Oswestry) was calculated and labeled as A scores. These patients were then rescored by assigning NPC as a good prognostic tumor and labeled as B scores. The predicted survival of scores A and B was compared with actual survival. Potential prognostic factors of survival were investigated using univariate and stepwise multivariate Cox regression analyses. Kaplan–Meier survival estimates, log-rank tests, and Cox regression analyses were done for all scoring systems A and B. The predictive values of each scoring system were calculated using post estimation after Cox regression analyses. Results Eighty-seven patients with spinal metastases from NPC were included in the study. The median overall survival for the whole cohort was 13 months (range: 1–120 months). In multivariate analysis, general condition ( p < 0.01), visceral metastases ( p < 0.01), and vertebral metastases ( p < 0.01) showed significant association with survival. The absolute score of all scoring systems was significantly associated with actual survival, which extended to the different prognostic subgroups of each scoring system. Log-rank test revealed that there were statistically significant differences in survival among the different prognostic groups of all scoring systems ( p < 0.01). Predictive value of survival by modified Tokuhashi score was the highest among all four scoring systems. Conclusions Patients with spinal metastases from NPC have good survival prognosis. All four scoring systems could be used to prognosticate these patients with a statistically significant association with actual survival. The modified Tokuhashi score is the best in doing so.