[Multiple myeloma and renal impairment].

Renal impairment (RI) is a common complication and it impacts on a survival of patients with systemic multiple myeloma (MM). In a cohort study in Akita, about 20-26% patients with MM showed RI at diagnosis and it was independently associated with overall survival. Cast nephropathy, amyloidosis, and monoclonal immunoglobulin deposition disease (Randall type) are known as three pathological findings of kidney in MM patients with RI. Recently, the term monoclonal gammopathy of renal significance (MGRS) was proposed because of a causal relationship between the monoclonal gammopathy and the renal damage. Bortezomib-based regimens may improve renal function in the majority of MM patients with RI. We discussed an epidemiology, clinic-pathological findings and treatments of MM with RI in this review.