Abstract: Multiple myeloma (MM) is the second commonest hematological malignant tumor. One of the most important and commonest organs damaged in MM is kidney, usually manifested as myeloma cast nephropathy (MCN) caused by a large number of serum free light chains (sFLCs) from malignant plasma cells. MCN is difficult to treat with poor prognosis, and is one of the main causes of early death in MM. Rapid reduction of sFLCs may improve the kidney function. High cut-off hemodialysis (HCO-HD) with the filters of large pore size can effectively clear the excessive sFLCs. HCO-HD combined with chemotherapy such as bortezomib lead to a tendency of better renal prognosis, but the economic benefit is yet controversial. The results of HCO-HD for MCN is inconsistent, if comparison is made with the results using high flux hemodialysis (HFHD). Currently, there is no standard HCO-HD protocol, and large-scale samples, long-term follow-up, and randomized controlled trials are required to evaluate the clinical outcomes of MCN patients treated by HCO-HD. This article reviews the pathogenesis of MCN, and the clinical application of HCO-HD in MCN.

Key words: High cut-off hemodialysis, Myeloma cast nephropathy, Acute kidney injury, Serum free light chains