Diagnostic and Prognostic Implications of Spine Magnetic Resonance Imaging at Diagnosis in Patients with Multiple Myeloma

PURPOSE: The aim of this study is to determine the diagnostic and prognostic role of baseline spinal magnetic resonance imaging (MRI) in patients with multiple myeloma. MATERIALS AND METHODS: We enrolled patients newly diagnosed with multiple myeloma from 2004-2011 at a single center. Abnormal MRI findings that were not detected in radiographs have been analyzed and categorized as malignant compression fractures or extramedullary plasmacytoma. The bone marrow (BM) infiltration patterns on MRI have been classified into five categories. RESULTS: A total of 113 patients with a median age of 65 years (range, 40 to 89 years) were enrolled in the study. Malignant compression fractures not detected in the bone survey were found in 26 patients (23.0%), including three patients (2.6%) with no related symptoms or signs. Extramedullary plasmacytoma was detected in 22 patients (19.5%), including 15 (13.3%) with epidural extension of the tumor. Of these 22 patients, 11 (50.0%) had no relevant symptoms or signs. The presence of malignant compression fractures did not influence overall survival; whereas non-epidural extramedullary plasmacytoma was associated with poor overall survival in the multivariate analysis (hazard ratio, 3.205; 95% confidence interval [CI], 1.430 to 9.845; p=0.042). During the follow-up for a median of 21 months (range, 1 to 91 months), overall survival with the mixed BM infiltrative pattern (median, 24.0 months; 95% CI, 22.9 to 25.1 months) was shorter than those with other patterns (median 56 months; 95% CI, 48.9 to 63.1 months; p=0.030). CONCLUSION: These results indicate that spine MRI at the time of diagnosis is useful for detecting skeletal lesions and predicting the prognosis in patients with multiple myeloma.