Akahane Koshi, Watanabe Atsushi, Furuichi Yoshiyuki, Somazu Shinpei, Oshiro Hiroko, Goi Kumiko, Sakashita Kazuo, Muramatsu Hideki, Hama Asahito, Takahashi Yoshiyuki, Koike Kenichi, Kojima Seiji, Sugita Kanji, Inukai Takeshi
Department of Pediatrics, Faculty of Medicine, University of Yamanashi, Yamanashi, Japan.
Department of Hematology and Oncology, Nagano Children's Hospital, Nagano, Japan.
Pediatr Transplant. 2019 May;23(3):e13378. doi: 10.1111/petr.13378. Epub 2019 Feb 20.
JMML is an aggressive hematopoietic malignancy of early childhood, and allogeneic HSCT is the only curative treatment for this disease. Umbilical cord blood is one of donor sources for HSCT in JMML patients who do not have an HLA-compatible relative, but engraftment failure remains a major problem. Here, we report two cases of JMML who were successfully rescued by HSCT from an HLA-mismatched parent after development of primary engraftment failure following unrelated CBT. Both patients had severe splenomegaly and underwent unrelated CBT from an HLA-mismatched donor. Immediately after diagnosis of engraftment failure, both patients underwent HSCT from their parent. For the second HSCT, we used RIC regimens consisting of FLU, CY, and a low dose of rabbit ATG with or without TBI and additionally administered ETP considering their persistent severe splenomegaly. Both patients achieved engraftment without severe treatment-related adverse effects. After engraftment of second HSCT, their splenomegaly was rapidly regressed, and both patients showed no sign of relapse for over 4 years. These observations demonstrate that HSCT from an HLA-mismatched parent could be a feasible salvage treatment for primary engraftment failure in JMML patients.
幼年型粒单核细胞白血病（JMML）是一种侵袭性的儿童早期造血系统恶性肿瘤，异基因造血干细胞移植（HSCT）是治疗该疾病的唯一治愈性方法。脐带血是没有HLA配型相合亲属的JMML患者HSCT的供体来源之一，但植入失败仍然是一个主要问题。在此，我们报告两例JMML患者，他们在非亲属脐带血移植后发生原发性植入失败，随后通过来自HLA不相合父母的HSCT成功获救。两名患者均有严重脾肿大，并接受了来自HLA不相合供体的非亲属脐带血移植。在诊断植入失败后，两名患者均接受了来自其父母的HSCT。对于第二次HSCT，我们使用了由氟达拉滨（FLU）、环磷酰胺（CY）和低剂量兔抗胸腺细胞球蛋白（ATG）组成的减低预处理方案（RIC），有或没有全身照射（TBI），并考虑到他们持续的严重脾肿大额外给予依替普酶（ETP）。两名患者均实现植入，且无严重的治疗相关不良反应。第二次HSCT植入后，他们的脾肿大迅速消退，两名患者在超过4年的时间里均无复发迹象。这些观察结果表明，来自HLA不相合父母的HSCT可能是JMML患者原发性植入失败的一种可行的挽救治疗方法。
