Prognostic significance of magnetic resonance imaging in patients with asymptomatic multiple myeloma.

Abstract
PURPOSE To assess the prognostic significance of magnetic resonance (MR) imaging in patients with newly diagnosed asymptomatic multiple myeloma. PATIENTS AND METHODS Thirty-eight consecutive patients with asymptomatic myeloma of low tumor mass and negative skeletal surveys underwent MR imaging of the thoracic and lumbosacral spine. The presence and patterns of marrow involvement were correlated with standard laboratory parameters and time to disease progression. RESULTS Nineteen patients (50%) had evidence of marrow involvement at spinal MR imaging. MR patterns of marrow involvement were classified as diffuse (five patients), variegated (nine), and focal (five). Patients with abnormal MR imaging studies required therapy after a median of 16 months, versus 43 months for those with normal MR studies (P < .01). CONCLUSION Abnormal marrow patterns were present in half of patients with asymptomatic myeloma. An abnormal MR study of the spine identified asymptomatic patients who were likely to require treatment earlier than those with a normal MR study. A normal MR pattern provided additional justification to defer institution of chemotherapy. However, MR imaging remains an investigational tool to stage patients with multiple myeloma until more data are accumulated.