The SORG nomogram accurately predicts 3‐ and 12‐months survival for operable spine metastatic disease: External validation

BACKGROUND AND OBJECTIVES: Externally validate the SORG12 nomogram and SORG classic algorithm at estimating survival in patients with spine metastatic disease, and compare predictive accuracy with other survival algorithms. METHODS: We received data from 100 patients who had surgery for spine metastatic disease at an external institution. Algorithms were accurate if the Area Under Curve (AUC) was >0.70, and we used Receiver Operating Characteristic (ROC) analysis to compare predictive accuracy with other algorithms. RESULTS: The SORG nomogram accurately estimated 3-months (AUC = 0.74) and 12-months survival (AUC = 0.78); it did not accurately estimate 1-month survival (AUC = 0.65). There was no difference in 1-month survival accuracy between the SORG nomogram and SORG classic algorithm (P = 0.162). The SORG nomogram was best at predicting 3-months survival, compared with the Tokuhashi score and SORG classic algorithm (P = 0.009). The SORG nomogram was best at predicting 12-months survival, compared with the Tomita score, Ghori score, Bauer modified score, Tokuhashi score, and SORG classic algorithm (P = 0.033). CONCLUSIONS: The SORG nomogram accurately estimated 3- and 12-months survival for operable spine metastatic disease, and is therefore, useful in clinical practice.