International Multidisciplinary Consensus Group for Malignant Spinal Cord Compression: recommendations for definitions, reporting items, and study endpoints for clinical trials and audits.

Abstract

Malignant spinal cord compression (MSCC) is a serious complication of spinal metastases and primary spinal tumours that can severely affect quality of life and overall survival. Clinical trials have used inconsistent definitions, criteria, and endpoints, limiting comparability. We conducted a Delphi consensus process following a systematic review of prospective MSCC trials from Jan 1, 2003, to Feb 26, 2024. From June 25, 2024, to Jan 11, 2025, experts from 20 countries participated in two survey rounds, 74 in round 1 and 71 in round 2. Consensus was defined as over 75% agreement. 49 statements reached consensus, including definitions for clinical, radiological, and impending MSCC using the Bilsky scale. Experts agreed on baseline and follow-up assessments, including pain, motor and sensory function, ambulation, and urinary and anal sphincter function. Standardised functional scales, response criteria, endpoint definitions, and timing of assessments were established. A core set of mandatory and secondary endpoints was defined for different MSCC scenarios, along with minimum reporting standards for surgery and radiotherapy toxicity. These recommendations aim to standardise future MSCC trials and audits to improve data consistency and comparability.