Prospective comparison of the accuracy of the New England Spinal Metastasis Score (NESMS) to legacy scoring systems in prognosticating outcomes following treatment of spinal metastases

Spine J. 2022 Jan;22(1):39-48. doi: 10.1016/j.spinee.2021.03.007. Epub 2021 Mar 16.

Abstract

Background context: We developed the New England Spinal Metastasis Score (NESMS) as a simple, informative, scoring scheme that could be applied to both operative and non-operative patients. The performance of the NESMS to other legacy scoring systems has not previously been compared using appropriately powered, prospectively collected, longitudinal data.

Purpose: To compare the predictive capacity of the NESMS to the Tokuhashi, Tomita and Spinal Instability Neoplastic Score (SINS) in a prospective cohort, where all scores were assigned at the time of baseline enrollment.

Patient sample: We enrolled 202 patients with spinal metastases who met inclusion criteria between 2017-2019.

Outcome measures: One-year survival (primary); 3-month mortality and ambulatory function at 3- and 6-months were considered secondarily.

Methods: All prognostic scores were assigned based on enrollment data, which was also assigned as time-zero. Patients were followed until death or survival at 365 days after enrollment. Survival was assessed using Kaplan-Meier curves and score performance was determined via logistic regression testing and observed to expected plots. The discriminative capacity (c-statistic) of the scoring measures were compared via the z-score.

Results: When comparing the discriminative capacity of the predictive scores, the NESMS had the highest c-statistic (0.79), followed by the Tomita (0.69), the Tokuhashi (0.67) and the SINS (0.54). The discriminative capacity of the NESMS was significantly greater (p-value range: 0.02 to <0.001) than any of the other predictive tools. The NESMS was also able to inform independent ambulatory function at 3- and 6-months, a function that was only uniformly replicated by the Tokuhashi score.

Conclusions: The results of this prospective validation study indicate that the NESMS was able to differentiate survival to a significantly higher degree than the Tokuhashi, Tomita and SINS. We believe that these findings endorse the utilization of the NESMS as a prognostic tool capable of informing care for patients with spinal metastases.

Keywords: Decision-making; NESMS; Prognostic score; SINS; Spinal metastases; Survival; Tokuhashi; Tomita.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cohort Studies
  • England
  • Humans
  • Prognosis
  • Prospective Studies
  • Retrospective Studies
  • Severity of Illness Index
  • Spinal Neoplasms* / therapy