“…Predictors used for SORG-MLA's prediction were manually collected from electronic chart review, 7 including primary cancer categorized as rapid growth, moderate growth, or slow growth tumors by Katigiri et al, 12 Eastern Cooperative Oncology Group (ECOG) performance scale, 13 presence of any Charlson comorbidities other than metastatic cancer, 14 American Spinal Injury Association (ASIA) impairment scale, 15 the presence of visceral (lung or liver), brain, or more than three spine-level metastases, whether using systemic therapy before the index treatment, body mass index (BMI), and the following nine preoperative laboratory values: hemoglobin (g/dL), platelet (×10 3 /μL), white blood cell (×10 3 /μL), absolute lymphocyte (×10 3 /μL), absolute neutrophil (×10 3 /μL), international normalized ratio, albumin (g/dL), alkaline phosphatase (IU/L), and creatinine (mg/dL). The same definitions were used for both the validation and development cohort.…”