Salvaged single-unit cord blood transplantation for 26 patients with hematologic malignancies not in remission

Treatments for patients with hematologic malignancies not in remission are limited, but a few clinical studies have investigated the effects of salvaged unrelated cord blood transplantation (CBT). We retrospectively studied 19 patients with acute leukemia, 5 with myelodysplastic syndrome (MDS with refractory anemia with excess blasts [RAEB]), and 2 with non-Hodgkin's lymphoma who received 1 CBT unit ≤2 loci human leukocyte antigen (HLA)-mismatched after undergoing myeloablative conditioning regimens between July 2005 and July 2014. All of them were in non-remission before transplantation. The infused total nucleated cell (TNC) dose was 4.07 (range 2.76-6.02)×107/kg and that of CD34+ stem cells was 2.08 (range 0.99-8.65)×105/kg. All patients were engrafted with neutrophils that exceeded 0.5×109/L on median day +17 (range 14-37 days) and had platelet counts of >20×109/L on median day +35 (range 17-70 days). Sixteen patients (61.5%) experienced pre-engraftment syndrome (PES), and six (23.1%) patients progressed to acute graft-versus-host disease (GVHD). The cumulative incidence rates of II-IV acute GVHD and chronic GVHD were 50% and 26.9%, respectively. After a median follow-up of 27 months (range 5-74), 14 patients survived and 3 relapsed. The estimated 2-year overall survival (OS), disease-free survival (DFS), and non-relapse mortality (NRM) rates were 50.5%, 40.3%, and 35.2%, respectively. Salvaged CBT might be a promising modality for treating hematologic malignancies, even in patients with a high leukemia burden.

针对未获得缓解的血液系统恶性肿瘤患者，当前治疗手段较为有限，目前已有少量临床研究探索了挽救性无关脐血移植（CBT）的应用效果。本研究回顾性分析了2005年7月至2014年7月期间的26例患者资料：其中急性白血病19例、骨髓增生异常综合征伴原始细胞增多型（RAEB）5例、非霍奇金淋巴瘤2例，所有患者均在接受清髓性预处理方案后，输注了1个人类白细胞抗原（HLA）配型错配≤2个位点的脐血单位。所有患者移植前均处于未缓解状态。输注的有核细胞总数（TNC）中位数为4.07×10^7/kg（范围2.76~6.02×10^7/kg），CD34+干细胞输注剂量中位数为2.08×10^5/kg（范围0.99~8.65×10^5/kg）。患者中性粒细胞植入中位时间为+17天（范围14~37天），植入判定标准为中性粒细胞计数＞0.5×10^9/L；血小板植入中位时间为+35天（范围17~70天），植入判定标准为血小板计数＞20×10^9/L。16例（61.5%）患者出现植入前综合征（PES），6例（23.1%）进展为急性移植物抗宿主病（GVHD）。Ⅱ~Ⅳ级急性GVHD与慢性GVHD的累积发生率分别为50%与26.9%。中位随访时间为27个月（范围5~74个月），其中14例患者存活，3例出现疾病复发。估算的2年总生存期（OS）、无病生存期（DFS）及非复发死亡率（NRM）分别为50.5%、40.3%与35.2%。挽救性无关脐血移植（CBT）或是治疗血液系统恶性肿瘤的颇具前景的手段，即便对于白血病负荷较高的患者亦适用。