Diagnosis and treatment of multiple myeloma and AL amyloidosis with focus on improvement of renal lesion

Multiple myeloma (MM) and AL amyloidosis are caused by the expansion of monoclonal plasma cells and secretion of dysproteinemia (Bence Jones protein and free light chain) and some patients require the hemodialysis. Myeloma kidney is mainly caused by the cast nephropathy of the distal tubuli, whereas, AL amyloid-protein is mainly deposited in glomeruli with massive fibrillar involvement. Therefore, almost MM patients presents a symptom of renal insufficiency, whereas, almost patients of AL amyloidosis present a nephrotic syndrome with severe hypoalbuminemia. These two diseases have some similar characteristics such as up-regulation of cyclin D1 gene by 11:14 chromosomal translocation. High-dose chemotherapy supported with autologous peripheral blood stem cells is effective for these two diseases. However, they are still difficult to be cured and require long-term disease control. In recent years, introduction of novel agents has changed their treatment strategies from the palliation therapy to the clinical cure.