- Patient must have myeloma that is measurable by either serum or urine evaluation of the monoclonal component or by assay of serum free light chains. Measurable disease is defined as one or more of the following: serum M-protein ≥ to 0.5 g/dl, urine M-protein ≥ 200 mg/24 h, and/or serum FLC assay: involved FLC level > 10 mg/dL with abnormal serum FLC ratio.