Revisiting Survival in the Treatment of Spinal Metastases from Lung Cancer in the Modern Era of Immunotherapy and Molecular Targeted Treatment (2017-2022)

STUDY DESIGN: Retrospective cohort. OBJECTIVE: To assess survival among patients with spinal metastases from lung cancer treated over a time period that accounts for advances in immunotherapy and targeted treatments. SUMMARY OF BACKGROUND DATA: The use of immunotherapy and targeted treatments has improved survival for patients with lung cancer, questioning whether secular trends have ushered in a new landscape in the field of spinal metastases. METHODS: We identified patients who underwent operative or non-operative treatment for spinal metastases (2017-22). The primary outcome was one-year survival. We used multivariable logistic regression analysis to adjust for confounders, including all variables abstracted as co-variates based on conceptual model. We also assessed for interactions between lung cancer and surgical intervention and surgical intervention and immunotherapy. RESULTS: We included 997 patients, with 228 (22.9%) possessing a primary lung cancer diagnosis. At one year, lung cancer was significantly associated with the odds of mortality (OR 2.01; 95% CI 1.44, 2.82). Surgical intervention (OR 0.70; 95% CI 0.53, 0.92), serum albumin of 3.5 g/dL or greater (OR 0.34; 95% CI 0.24, 0.47) and ambulatory status (OR 0.47; 95% CI 0.34, 0.64) were all significantly associated with reduced likelihood of mortality. There was no significant association between immunotherapy and one-year survival (OR 0.82; 95% CI 0.61, 1.11; P=0.19). At 30- (OR 0.55; 95% CI 0.29, 0.98) and 90-days (OR 0.65; 95% CI 0.45, 0.93) immunotherapy was significantly associated with survival. CONCLUSIONS AND RELEVANCE: One-year survival in the cohort of patients with spinal metastases derived from lung cancer was significantly lower than that of metastases from other cancers. Surgical intervention did not mitigate this fact. Immunotherapy may exert an effect on near-term survival only. The signals for some of these temporal changes are robust enough to warrant consideration of their impact on traditional prognostic utilities in the future. LEVEL OF EVIDENCE: III.