Predictors of Outcomes and a Scoring System for Estimating Survival in Patients Treated With Radiotherapy for Metastatic Spinal Cord Compression From Small-Cell Lung Cancer

Abstract

PurposeTo identify prognostic factors and create a survival score to facilitate individualized care of patients with metastatic spinal cord compression (MSCC) from small-cell lung cancer (SCLC). Patients and MethodsRadiation regimen plus 9 factors were retrospectively evaluated in 120 patients irradiated for MSCC from SCLC for overall response, improvement of motor deficits, postradiotherapy ambulatory status, local control of MSCC, and overall survival (OS). Factors included age, interval diagnosis of SCLC to radiotherapy (RT) of MSCC, visceral metastases, further bone metastases, gender, time developing motor deficits, pre-RT ambulatory status, number of affected vertebrae, and Eastern Cooperative Oncology Group performance status (ECOG PS). ResultsImprovement of motor deficits showed significant associations with ECOG PS 1-2 (P = .018); time developing motor deficits achieved borderline significance (P = .059). Post-RT ambulatory status was significantly associated with slower development of motor dysfunction (P = .003), ambulatory status (P < .001), and ECOG PS 1-2 (P < .001). No factor was significantly associated with overall response and local control. On multivariate analysis, OS was significantly associated with interval from SCLC diagnosis to RT of MSCC (P = .004), visceral metastases (P < .001), ambulatory status (P = .002), and ECOG PS (P = .002). For the survival score, 6-month OS rates related to each of these factors were divided by 10. Patient scores were obtained by adding these factors' scores. Three groups were defined (5, 7-13, and 15-17 points) with 6-month OS rates of 0, 18%, and 77%, respectively (P < .001). ConclusionPredictors of various outcomes were identified and a survival score was created that can support physicians aiming to create personalized treatments to patients with MSCC from SCLC.