Accuracy of the revised Tokuhashi score in predicting survival in patients with metastatic spinal cord compression (MSCC)

Abstract

Purpose: The revised Tokuhashi score has been widely used to evaluate indications for surgery and predict survival in patients with metastatic spinal disease. Our aim was to analyse the actual survival time of patients treated for metastatic spinal cord compression (MSCC) in comparison with the predicted survival based on the revised Tokuhashi score. This would thereby allow us to determine the overall predictive value of this scoring system.

Methods: This study was a semi-prospective clinical study of all patients with MSCC presenting to our unit over 8 years-data from October 2003 to December 2009 were collected retrospectively and from December 2009, all data collected prospectively to October 2011. Patients were divided into three groups--Group 1 (Tokuhashi score 0-8, n = 84), Group 2 (Tokuhashi score 9-11, n = 83) and Group 3 (Tokuhashi score 12-15, n = 34). Data collected included demographic data, primary tumour histology, surgery type and complications, neurological outcome (Frankel grade) and survival.

Results: A total of 233 patients with MSCC were managed surgically in our unit during this time. Out of these complete data were available on 201 patients for analysis. Mean age of patients was 61 years (range 18-86; 127 M, 74 F). The primary tumour type was Breast (n = 29, 15 %), Haematological (n = 28, 14 %), Renal (n = 26, 13 %), Prostate (n = 26, 13 %), Lung (n = 23, 11 %), Gastro-intestinal (n = 11, 5 %), Sarcoma (n = 9, 4 %) and others (n = 49, 24 %). All patients included in the study had surgical intervention in the form of decompression and stabilisation. Posterior decompression and stabilisation was performed in 171 patients (with vertebrectomy in 31), combined anterior and posterior approaches were used in 18 patients and 12 had an anterior approach only. The overall complication rate was 19 % (39/201)--the most common being wound infection (n = 15, 8 %). There was no difference in the neurological outcome (Frankel grade) between Groups 1 and 2 (p = 0.34) or Groups 2 and 3 (p = 0.70). However, there was a significant difference between Groups 1 and 3 (p = 0.001), with Group 3 having a significantly better neurological outcome. Median survival was 93 days in Group 1, 229 days in Group 2 and 875 days in Group 3 (p = 0.001). The predictive value between the actual and predicted survival was 64 % (Group 1), 64 % (Group 2) and 69 % (Group 3). The overall predictive value of the revised Tokuhashi score using Cox regression for all groups was 66 %.

Conclusion: We would conclude that although the predictive value of the Tokuhashi score in terms of survival time is at best modest (66 %), the fact that there were statistically significant differences in survival between the groups looked at in this paper indicates that the scoring system, and the components which it consists of, are important in the evaluation of these patients when considering surgery.

Fig. 1

Kaplan Meier survival curve for all three groups