In The spine journal : official journal of the North American Spine Society
BACKGROUND CONTEXT : Pre-operative survival estimation in spinal metastatic disease helps determine the appropriateness of invasive management. The SORG ML ninety-day and one-year machine learning algorithms for survival in spinal metastatic disease were previously developed in a single institutional sample but remain to be externally validated.
PURPOSE : The purpose of this study was to externally validate these algorithms in an independent population from another institution STUDY DESIGN/SETTING: Retrospective study at a large, tertiary care center PATIENT SAMPLE: Patients 18 years or older who underwent surgery between 2003 and 2016 OUTCOME MEASURES: Ninety-day and one-year mortality METHODS: Baseline characteristics of the validation cohort were compared to the developmental cohort for the SORG ML algorithms. Discrimination (c-statistic and receiver operating curve), calibration (calibration slope, intercept, calibration plot, and observed proportions by predicted risk groups), overall performance (Brier score), and decision curve analysis were used to assess the performance of the SORG ML algorithms in the validation cohort.
RESULTS : Overall, 176 patients underwent surgery for spinal metastatic disease, of which 44 (22.7%) experienced ninety-day mortality and 99 (56.2%) experienced one-year mortality. The validation cohort differed significantly from the developmental cohort on primary tumor histology, metastatic tumor burden, previous systemic therapy, overall comorbidity burden, and pre-operative laboratory characteristics. Despite these differences, the SORG ML algorithms generalized well to the validation cohort on discrimination [c-statistic 0.75-0.81 for ninety-day mortality and 0.77-0.78 for one-year mortality], calibration, Brier score, and decision curve analysis.
CONCLUSION AND RELEVANCE : Initial results from external validation of the SORG ML ninety-day and one-year algorithms for survival prediction in spinal metastatic disease suggest potential utility of these digital decision aids in clinical practice. Further studies are needed to validate or refute these algorithms in large patient samples from prospective, international, multi-institutional trials.
Karhade Aditya V, Ahmed Ali K, Pennington Zach, Chara Alejandro, Schilling Andrew, Thio Quirina C B S, Ogink Paul T, Sciubba Daniel M, Schwab Joseph H
external validation, machine learning, neurosurgery, ninety-day, one-year, orthopaedic surgery, prediction, prognosis, spine metastasis, spine surgery, survival