Predictors of Survival After Emergent Surgical Decompression for Acutely Presenting Spinal Metastasis

Metastatic spinal tumors represent 90% of spinal masses and present variably with slow progression and/or rapid symptomatic worsening. Several prognostic scoring systems have been proposed. However, patients presenting acutely and requiring emergent surgery represent a unique subset of patients with different prognostic indicators.

All cases of symptomatic spinal metastases requiring emergent surgery between 2010 and 2021 at our institution were retrospectively reviewed. Survival time from date of surgery to death or last follow-up was calculated. Patients were stratified on the basis of survival for more or less than 6 months after surgery. Multivariate logistic regression was used to develop a model predicting probability of mortality at 6 months.

Forty-four patients satisfied inclusion criteria. Mean age at presentation was 60.4 ± 11.8 years with a median survival time of 6.5 [1.9-19.5 interquartile range] months. On univariate analysis, higher Tokuhashi score, Karnofksy performance scale (KPS), and lower modified McCormick scale were significantly associated with 6-month survival (P = 0.018, P < 0.001, P = 0.002, respectively). Preoperative American Spinal Injury Association grade and Spine Instability Neoplastic Score scores were not associated with survival. Multivariate analysis found KPS significantly correlated with survival (0.91 odds ratio, 0.85-0.98, 95% confidence interval, P = 0.011) at 6 months and that a stepwise regression model derived from KPS and Tokuhashi score demonstrated the highest predictive accuracy for 6-month survival (area under the curve = 0.843, Akaike information criterion = 37.1, P = 0.0039).

KPS and Tokuhashi scores most strongly correlated with 6-month survival in patients presenting with acutely symptomatic spinal metastases. These findings underscore the importance of baseline functional status and overall tumor burden on survival and may be useful in preoperative evaluation and surgical decision making for acutely presenting spinal metastases.