Risk Factors for Spinal Cord Compression on MRI in Oncology: Enhancing Diagnostic Yield.

Abstract

Background and purpose: Epidural spinal cord compression (ESCC) is an important cause of disability among cancer patients. Early detection is crucial for optimizing clinical outcomes. MRI is the preferred imaging modality for ruling out ESCC and frequently requested in radiology departments, particularly in the emergent setting. However, data on the efficacy and diagnostic yield of total spine MRI for diagnosis of ESCC in oncology patients remain limited. This study evaluates the frequency of positive findings and associated risk factors in a tertiary cancer center.

Materials and methods: This retrospective study included patients who underwent total spine MRI for assessment of ESCC over a 3-year period. A standardized non-contrast MRI protocol was utilized. Clinical and imaging data, including patient demographics (sex, age), tumor pathology, tumor-node-metastasis (TNM) stage, ESCC grade, symptoms, prior treatments (radiotherapy, surgery, chemotherapy), and ordering physician/department, were retrospectively reviewed. Patients were categorized into 2 groups based on presence or absence of cord compression (ESCC 2 or 3). Associations between ESCC and other variables were assessed via Wilcoxon rank sum test, Pearson's chi-squared test, and Fisher's exact test. Statistical significance was defined as p < 0.05.

Results: Among 289 patients (median age 66 years, 148 females) and 300 total spine MRI examinations, ESCC was detected in 18 cases (6.0%). Significant associations with ESCC included advanced TNM stage (p = 0.03) and prior treatments, such as radiation to the site of compression (p = 0.002), decompression surgery (p = 0.01), and recent systemic chemotherapy (p < 0.001). Bone metastases to the spine on body CT exams performed within 2 weeks prior to MRI also correlated with ESCC (p < 0.001). Notably, no ESCC cases occurred in patients without spine bone metastases on recent body CT, or in those with less than stage IV disease. Patient symptoms did not correlate with ESCC presence (p = 0.3).

Conclusions: This study suggests that the diagnostic yield of total spine MRI for ESCC in oncology patients is relatively low and may be improved by refining selection criteria. Patients with advanced-stage disease, prior spinal interventions, and bone metastases on recent body CT may be at higher risk.

Abbreviations: Epidural spinal cord compression (ESCC), tumor-node-metastasis (TNM).