You have to be registered and logged in for purchasing articles.

Abstract

Serum Free Light Chain Predict Overall Survival and Response to Therapy in Patients with Newly Diagnosed Multiple Myeloma by Yanis Meddour, Momahed C. Rahali, Salah E. Belakehal, Fatma Z. Ardjoun, Samia Chaib, Reda Djidjik

Background: Multiple myeloma is characterized by underlying clinical and biological heterogeneity, which translates to variable responses to treatment and outcome.
Methods: To assess the roles of serum free light chain (sFLC) and K/L FLC ratio (rFLC) in the diagnoses and prognoses of multiple myeloma (MM), sFLC levels and K/L ratios were measured in 112 patients with newly diagnosed multiple myeloma using the Freelite automated immunoassay.
Results: Abnormal sFLC and/or rFLC levels were detected 99.1% of the patients. The baseline sFLC predicted the overall survival (OS). The median OSs were not reached (NR) and were 30 months in the low sFLC group (sFLC-K < 132 mg/L or sFLC-L < 342 mg/L) and the high sFLC group (sFLC-K ≥ 132 mg/L or sFLC-L ≥ 342 mg/ L) (p < 0.001), respectively. Similarly, the rFLC successfully predicted the OS times of 29 months for group A (rFLC ≤ 0.03 or ≥ 32) and NR for group B (0.03 < rFLC < 32) (p < 0.001). According to the response to treatment and sFLC ratio, significant differences in the OSs were observed between the partial response group and other patients, (respectively, OS median = 28 months vs. NR, log rank p < 0.001). Additionally, the patients were further stratified into two groups using the novel poor-prognosis factors (rFLC > 32 or < 0.03) combined with the International Staging System parameters (beta2-microglobulin, albumin), i.e., a low-risk group (those with zero or one factor) and a high-risk group (those with two or three factors). The median OSs for the low- and high-risk groups were NR and 29 months, respectively (p = 0.001).
Conclusions: The sFLC assay was extremely sensitive in the diagnosis of MM. In addition to its strong prognosis value, it could be a predictor of response to therapy.

DOI: 10.7754/Clin.Lab.2017.171040