Successful treatment with lenalidomide of secondary multiple myeloma with extramedullary liver plasmacytoma in a renal transplant recipient: A case report and review of the literature.

Multiple myeloma (MM) represents a rare form of post-transplantation lymphoproliferative disorder, and the presence of plasma cells in the liver is generally associated with aggressive forms of MM. In the present study, an unusual case of extramedullary plasmacytoma, affecting the liver and vertebrae of a recipient of a renal transplant, is reported. The patient had been previously treated with bortezomib for an MM following renal transplantation, as diagnosed by percutaneous needle biopsy of the hepatic lesion. He was then treated with 5 cycles of RCD regimen (lenalidomide, 25 mg, days 1-21; cyclophosphamide. 50-100 mg, days 1-21; and dexamethasone, 20 mg, days 1, 8, 15 and 22). The patient achieved partial clinical remission without any severe therapy-associated toxicity effects, indicating that lenalidomide is an effective and safe treatment for extramedullary liver plasmacytoma in renal recipients. In conclusion, the present case study indicated that the RCD regimen was effective and safe in the treatment of relapsed and refractory MM.