Allogeneic hematopoietic stem cell transplantation (HSCT) is widely used for high-risk acute lymphoblastic leukemia (ALL) patients in their first complete remission (CR1), and for relapsed patients in second complete remission (CR2).

We retrospectively analyzed data for 67 children with ALL, from a cancer center in a low/middle income country, who had undergone HSCT from human leukocyte antigen (HLA)-matched sibling donors (MSDs) using myeloablative conditioning (MAC) regimens, between 2007 and 2020, describing the survival outcome and relapse probability after achieving CR1 and CR2 and determining outcome differences in relation to indications for HSCT in patients transplanted in CR1. All patients had achieved a negative minimal residual disease prior to transplant (<0.01%).

Forty-six patients (68.7%) were in CR1; 25 had adverse cytogenetics, including 18 patients with Philadelphia chromosome-positive ALL (Ph-positive ALL), and 21 had poor induction response. The 5-year overall survival (OS), event-free survival (EFS) and cumulative incidence of relapse (CIR) for the whole cohort were 56.1% (95% CI, 42.8%-69.4%), 49% (95% CI, 35.7%-62.3%) and 33.5% (95% CI, 21.7%-45.8%), respectively with better EFS and CIR for CR1 transplants compared to CR2 transplants (P=0.02 and P=0.03, respectively). Patients with Ph-positive ALL had better 5-year OS, EFS and non-relapse mortality (NRM) compared with other CR1 transplants (P=0.015, P=0.009 and P=0.028, respectively).

Hematopoietic stem cell transplantation from MSD for ALL in CR1 group had superior outcomes compared to CR2 group and was apparently a curable option for Ph-positive ALL without an increased risk of non-relapse mortality. Poorer survival rates and higher relapse probabilities were associated with HSCT conducted to patients who had a poor response to induction therapy or suffered a relapse.

异基因造血干细胞移植 (HSCT) 广泛用于首次完全缓解 (CR1) 的高危急性淋巴细胞白血病 (ALL) 患者和第二次完全缓解 (CR2) 的复发患者。

我们回顾性分析了来自中低收入国家癌症中心的 67 名 ALL 儿童的数据，这些儿童在 2007 年之间使用清髓性预处理 (MAC) 方案接受了来自人类白细胞抗原 (HLA) 匹配的同胞供体 (MSD) 的 HSCT和 2020 年，描述实现 CR1 和 CR2 后的生存结果和复发概率，并确定 CR1 移植患者与 HSCT 适应症相关的结果差异。所有患者在移植前均达到阴性微小残留病（<0.01%）。

46 名患者 (68.7%) 处于 CR1；25例细胞遗传学不良，其中费城染色体阳性ALL（Ph-positive ALL）18例，诱导反应不良21例。整个队列的5年总生存期（OS）、无事件生存期（EFS）和累计复发率（CIR）分别为56.1%（95% CI，42.8%-69.4%）、49%（95% CI , 35.7%-62.3%) 和 33.5% (95% CI, 21.7%-45.8%)，与 CR2 移植相比，CR1 移植的 EFS 和 CIR 更好（分别为 P=0.02 和 P=0.03）。与其他 CR1 移植相比，Ph 阳性 ALL 患者的 5 年 OS、EFS 和非复发死亡率（NRM）更好（分别为 P=0.015、P=0.009 和 P=0.028）。

与 CR2 组相比，来自 MSD 的 ALL 造血干细胞移植治疗 CR1 组的​​结果优于 CR2 组，显然是 Ph 阳性 ALL 的一种可治愈选择，且不会增加非复发死亡率的风险。较差的存活率和较高的复发概率与对诱导治疗反应不佳或复发的患者进行 HSCT 相关。