Department of Medicine, Division of Hematology-Oncology, Case Comprehensive Cancer Center, University Hospitals Case Medical Center, Cleveland, OH 44106, USA.
Bone Marrow Transplant. 2012 Sep;47(9):1212-6. doi: 10.1038/bmt.2011.244. Epub 2011 Dec 12.
Plasma cell myeloma, characterized by clonally aberrant plasma cells that produce abnormal monoclonal Igs, is the most common indication for autologous hematopoietic progenitor cell transplantation (AHPCT) in North America. We observed appearance of new monoclonal gammopathies different from the original protein in the post-AHPCT setting and termed this condition 'secondary MGUS' (monoclonal gammopathy of undetermined significance). Hence, we performed a retrospective, single institution review of serum protein electrophoresis/immunofixation electrophoresis data in 92 AHPCT recipients from the period 2000-2009. In all, 22 of 92 patients (24%) undergoing AHPCT met criteria for secondary MGUS. Contrary to previous studies, often referred to as 'abnormal protein banding,' we did not observe this condition as a favorable prognostic indicator in affected patients when compared with the control group (P=0.686). However, we did note that a subgroup of the study cohort who developed secondary MGUS after a prolonged latency (>10 months) had an improved median OS compared with the remainder of the study cohort (75 months vs 41 months, P=0.005). As there have been significant advancements in understanding the pathobiology and clinical significance of MGUS, we believe that secondary MGUS merits dedication of resources for investigation to determine its true clinical relevance, prognostic value and pathophysiology.
浆细胞骨髓瘤是一种以产生异常单克隆 Ig 的克隆性异常浆细胞为特征的疾病，是北美进行自体造血祖细胞移植（AHPCT）的最常见指征。我们在 AHPCT 后观察到与原始蛋白不同的新单克隆丙种球蛋白血症，并将这种情况称为“继发性 MGUS”（意义未明的单克隆丙种球蛋白病）。因此，我们对 2000 年至 2009 年期间进行 AHPCT 的 92 名患者的血清蛋白电泳/免疫固定电泳数据进行了回顾性、单机构研究。在接受 AHPCT 的 92 名患者中，共有 22 名（24%）符合继发性 MGUS 的标准。与以往的研究不同，我们没有观察到这种情况作为受影响患者的有利预后指标，与对照组相比（P=0.686）。然而，我们确实注意到，研究队列中有一小部分患者在较长潜伏期（>10 个月）后发生继发性 MGUS，与研究队列的其余部分相比，中位 OS 得到改善（75 个月 vs 41 个月，P=0.005）。由于对 MGUS 的病理生物学和临床意义的理解取得了重大进展，我们认为继发性 MGUS 值得投入资源进行研究，以确定其真正的临床相关性、预后价值和病理生理学。
