31. Development of clinical prognostic models for postoperative survival and quality of life in patients with surgically treated metastatic epidural spinal cord compression

Abstract

BACKGROUND CONTEXT Surgery is generally considered for patients with metastatic epidural spinal cord compression (MESCC) with a life expectancy of at least 3 months. No existing clinical prognostic models (CPMs) of survival are consistently used, and no CPMs exist which predict quality of life (QoL) following surgical treatment. These knowledge gaps are important given the challenges involved in managing MESCC. PURPOSE We aimed to develop the first CPMs of postoperative survival and QoL, using the transparent reporting of a multivariable prediction model for individual prognosis or diagnosis (TRIPOD) guidelines, and based on a large sample of prospective data of surgical patients with MESCC. STUDY DESIGN/SETTING Cohort study (retrospective analysis of prospectively collected data). PATIENT SAMPLE A total of 258 patients with MESCC who underwent surgical treatment. OUTCOME MEASURES There were two outcome measures: (1) the 1-year survival measured as the number of postoperative days until death from any cause; (2) the achievement of the minimal clinical important difference of 0.06 on the postoperative EQ-5D scores at different time frames. METHODS Using TRIPOD guidelines and data from 258 patients (AOSpine North America (NA) MESCC study and Nottingham MESCC registry), we created 1-year survival and QoL CPMs using Cox model and logistic regression with manual backward elimination. The outcome measure for QoL was the minimal clinical important difference (MCID) in EQ-5D scores. Internal validation involved 200 bootstrap iterations; calibration and discrimination were evaluated. RESULTS Longer survival was associated with higher SF-36 physical component score (PCS) (HR: 0.96) whereas primary tumor other than breast, thyroid, and prostate (unfavorable, HR: 2.57; others, HR: 1.20), organ metastasis (HR: 1.51), male sex (HR: 1.58), and preoperative radiotherapy (HR: 1.53) were not (c-statistic: 0.69, 95% CI: 0.64-0.73). KPS CONCLUSIONS We developed and internally validated the first CPMs of survival and QoL at 3 months postoperatively in patients with MESCC using TRIPOD guidelines. A web-based calculator is available ( http://spine-met.com ) to assist clinical decision-making in this complex patient population. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.