Optimization of the Revised Tokuhashi Scoring System: New Prognostic Criteria for Metastatic Spinal Tumor in Surgical Cases

INTRODUCTION: The revised Tokuhashi scoring system has been used to predict survival in patients with metastatic spinal tumors. Because of the rapid progress of cancer therapy, the original criteria of the revised Tokuhashi scoring system became in recent years unsuitable. The study aim was to evaluate the validity of the revised Tokuhashi scoring system in patients who underwent spinal surgery and to establish new prognostic criteria. METHODS: The study enrolled 85 patients with metastatic spinal tumors who underwent spinal surgery. The patients' survival outcomes in October 2019 were as follows: 57 patients died; 10 were alive; and 18 had unknown prognoses. The study evaluated the validity of the Tokuhashi scoring system, and established and validated the new prognostic criteria. RESULTS: The accuracies of the Tokuhashi scoring system were 66.7% in the short-term group, 60% in the midterm group, and 100% in the long-term group. Among the patients who died, the survival period and total score were significantly correlated. Total score cutoff point was six points in the patients whose predicted survival was <6 months. Total score cutoff point was eight points in the patients whose predicted survival was ≥1 year. CONCLUSIONS: As the prognosis of patients has improved in recent years, the original criteria of the revised Tokuhashi scoring system have been questioned as to their suitability to current treatments. Especially, the survival period among the patients with total scores of 7 and 8 points was not accurate. According to this study, the new prognostic criteria of the revised Tokuhashi scoring system were set to 0 to 6 points for the short-term group, 7 points for the midterm group, and 8 to 15 points for the long-term group.