The Tokuhashi score: effectiveness and pitfalls

Purpose: Accurate survival estimation is prerequisite to determine the most appropriate treatment for patients with metastatic spine disease. Several authors have proposed classification systems analyzing clinical and radiological parameters, such as, performance status, metastasis localization, and primary tumor histotype, but the modified Tokuhashi score (mTS) is the most widely used. Although it is regarded as one of the most complete and accurate systems, it does not take the effectiveness of new therapeutic strategies into consideration, contributing to a progressive loss of accuracy. The purpose of this review is to verify the ability of the mTS to accurately estimate metastatic spine patient survival, nearly 10 years after it was introduced. Methods: A literature review was conducted to evaluate mTS accuracy to predict metastatic spine patient survival. Results: Ten studies were selected, representing 1686 patients. The total predictive accuracy of the mTS was 63.00 %; for patients expected to survive less than 6 months (group I), it was 64.10 %; 6–12 months (group II), 55.32 %; and more than 12 months (group III), 77.21 %. A progressive decrease in accuracy over time was statistically significant in groups I and II. Conclusions: The mTS is suggestive of actual survival for patients with a good prognosis. It is less accurate for patients with an estimated survival of less than 12 months. The decreasing trend in mTS accuracy over time will likely further reduce mTS utility. An important opportunity exists to develop new instruments to assist spine surgeons and oncologists to choose appropriate surgical or non-surgical treatment modalities for patients with metastatic spine disease.