Comparing the Accuracy of Seven Scoring Systems in Predicting Survival of Lung Cancer Patients With Spinal Metastases: An External Validation From Two Centers

Retrospective case series. OBJECTIVE. To investigate the accuracy of seven scoring systems for the prediction of survival in lung cancer patients with spinal metastases (SPM). SUMMARY OF BACKGROUND DATA. Although survival scoring systems have been developed for surgical decision-making, the reliability and validity of these models are unclear for specific cancer types. As the prevalence of patients with lung cancer increases, it is imperative to determine the accuracy of these models for lung cancer patients with SPM. MATERIALS AND METHODS. This is a retrospective study of a cohort of lung cancer patients with SPM who underwent spine surgery between 2019 and 2021 at two centers. The optimal area under the curve (AUC) was calculated to evaluate the accuracy of seven candidate scoring systems at 3, 6, and 12 months. Calibration and decision curve analysis was used for further validation. RESULTS. A total of 166 patients (mean age: 58.98±10.94; 105 males and 61 females) with SPM were included. The median postoperative survival was 12.87±0.93 months. The modified Bauer score, revised Tokuhashi score, Linden score, Tomita score, the Skeletal Oncology Research Group nomogram, and the New England Spinal Metastasis Score in prediction survival at 3, 6, and 12 months showed a slightly weaker AUC (range 0.464–0.659). The AUC of the Katagiri-New score in predicting 1-year survival for lung cancer patients was the highest (0.708; range 0.619–0.798). The decision curve analysis showed that the Katagiri-New score led to a greater net benefit than the strategies of changing management for all patients or none of the patients. CONCLUSIONS. This study suggests that the most commonly used models have limitations in predicting survival in patients undergoing spinal surgery for metastatic lung cancer and underestimate survival. In this sample of lung cancer patients, the Katagiri-New Scoring system score had the best performance in predicting 1-year survival. LEVEL OF EVIDENCE. 4.