Prognostic Value of Serum Free Light Chains Measurements in Multiple Myeloma Patients.

Our findings confirm the observations that the sFLCR has a major role in the survival of MM patients. A cut-off of sFLCR≥47 was shown to have an independent prognostic value at diagnosis, and a proposed "New Staging System" allows an accurate and simple method to risk stratify MM patients. Furthermore, because achievement of sCR was shown to represent a response state deeper than conventional CR resulting in greater OS and DFS, our study supports the continuity of sFLC ratio as part of the response criteria for MM patients.