Department of Clinical Biochemistry, INFIBIOC, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, Argentina.
Clin Chem Lab Med. 2012 Apr 24;50(6):1093-7. doi: 10.1515/cclm-2011-0544.
To establish stringent complete remission (SCR) in patients with multiple myeloma (MM), it is currently recommended to obtain a normal serum free light chains (sFLC) ratio. The appearance of serum oligoclonal bands (OB) after autologous stem cell transplantation (ASCT) is considered a favorable prognostic factor. The objective of this study was to examine sFLC for assessing SCR in patients with MM, and ASCT with OB. We also examined how capillary electrophoresis (CE) compares with agarose gel electrophoresis (Aga) in identifying oligoclonal bands.
Out of 238 patients studied in our institution between April 1992 and December 2008 a serum protein electrophoresis (SPE) was performed by means of CE and sFLC determination on 37 patients with MM in complete remission (CR), ASCT and OB presence were assigned by conventional Aga electrophoresis and IF.
Statistically significant differences (SSD) were found when comparing CE vs. Aga, regarding BO visualization in SPE, favoring the latter. In connection with sFLC, the group of patients with an abnormal ratio presented elevated values in the γ-globulin zone of the SPE, whereas the group of patients with a normal ratio of sFLC presented with normal values resulting in SSD between the groups.
It is essential to perform immunofixation to certify the presence of OB, especially if CE is used as it is difficult to distinguish them using this method. A normal sFLC was observed in most of the patients with OB and normal values of the SPE γ-globulin zone. The above-mentioned information might demonstrate a limitation of sFLC test in SCR evaluation for patients with MM, ASCT and CR if OB has been detected.
为了使多发性骨髓瘤（MM）患者达到严格的完全缓解（SCR），目前建议获得正常的血清游离轻链（sFLC）比值。自体干细胞移植（ASCT）后血清寡克隆带（OB）的出现被认为是一个有利的预后因素。本研究的目的是检查 sFLC 以评估 MM 患者和 ASCT 伴有 OB 的 SCR。我们还检查了毛细管电泳（CE）在识别寡克隆带方面与琼脂糖凝胶电泳（Aga）的比较。
在我们机构于 1992 年 4 月至 2008 年 12 月期间研究的 238 名患者中，对 37 名处于完全缓解（CR）的 MM 患者进行了血清蛋白电泳（SPE），通过 CE 和 sFLC 测定，使用传统的 Aga 电泳和 IF 确定 ASCT 和 OB 的存在。
CE 与 Aga 相比，在 SPE 中 OB 的可视化方面存在统计学显著差异（SSD），后者具有优势。关于 sFLC，异常比值组患者 SPE 的γ球蛋白区呈现出升高的值，而 sFLC 比值正常的组患者呈现出正常的值，导致组间 SSD。
进行免疫固定以证明 OB 的存在是至关重要的，尤其是在使用 CE 时，因为很难用这种方法区分它们。大多数 OB 和 SPE γ球蛋白区正常的患者中观察到正常的 sFLC。上述信息可能表明，如果检测到 OB，sFLC 测试在评估 MM、ASCT 和 CR 患者的 SCR 方面存在局限性。
