Can leptomeningeal myelomatosis be predicted in patients with IgD multiple myeloma?

Involvement of the central nervous system (CNS) by multiple myeloma (MM) is rare. Immunoglobulin D (IgD) MM represents only 1% to 2% of all MM patients. Previous reports show a disproportionate number of patients with IgD MM with leptomeningeal myelomatosis (LMM). Several biological markers have been associated with LMM. The development of LMM in a woman with IgD MM is reported. Our patient should be considered as having a high-risk of CNS disease based on: (i) presence of IgD-lambda MM; (ii) high myeloma burden (stage III); (iii) additional extramedullary disease; (iv) presence of circulating plasma cells, some with plasmablastic morphology; and (v) CD56-negative immunophenotype. The association between these features of MM reported previously and a high risk of LMM is reviewed. Studies including patients with these features are warranted to confirm their attributed LMM risk and to investigate the role of prophylactic chemoradiotherapy in this clinical setting. © 2010 Elsevier Ltd. All rights reserved.