Plasmocytomes intraduraux extramédullaires

Direct involvement of the nervous system in multiple myeloma is rare. A 73-year-old woman was admitted to our department because of cruralgia, sciatica, lumbar back pain and progressive difficulty walking. She had been treated for IgA-kappa-type multiple myeloma since ten months and achieved a very good partial response (VGPR) after eight cycles of VMP (bortezomib, melphalan, prednisone) regimen. Blood tests showed that she is still in VGPR. On medullary magnetic resonance imaging, she had multiple intradural extramedullary plasmacytomas involving cauda equina nerve roots. The cerebrospinal fluid examination revealed the presence of 120 dystrophic plasma cells per cubic millimeters, an elevated protein level, and an IgA-kappa monoclonal peak. Intradural and extramedullary plasmacytomas are rare entities whose treatment remains to be defined.