儿童急性早幼粒细胞白血病PML-RARα融合基因跟踪检测的临床意义(英文)

Signif icance of kinetic detection of the PML2RARα fusion gene in children with acute promyelocytic leukemia

摘要:

目的 探讨跟踪检测急性早幼粒细胞白血病 (APL)特有的PML RARα融合基因在发现APL早期复发和指导APL临床治疗方面的意义。方法 1 0例APL患儿用全反式维甲酸 (ATRA)和 (或 )其它化疗药物进行诱导缓解、巩固治疗和维持治疗 ,并进行随访。在病程的不同阶段采集骨髓标本进行形态学检查 ,并应用RT PCR方法检测PML RARα融合基因。结果 随访时间为 1 4～ 1 5 6月 (中位时间 4 2月 ) ,5年无病生存率为 5 6 .0 %±1 6 .5 %。 1 0例APL患儿完全缓解 (CR)率为 90 % ,早期死亡 1例。 9例CR病人中 4例在CR后 1 4～ 4 2月复发 ,4例在连续完全缓解 4～ 5年后已停药 ,停止治疗时间为 1 8～ 96月。 1例CR ,仍在继续治疗中。 9例CR患儿中 ,8例在病程中PML RARα转为阴性 ,1例持续阳性。 4例复发病人中 ,2例复发前持续阳性 ,2例在病程中由阴性转为阳性。 5例仍生存的患儿中 ,1例在病程中PML RARα由阴性转为阳性 ,2例分别在持续完全缓解 36和 4 2月仍呈阳性 ,这 3例患儿经治疗干预后均转阴 ,且长期生存。结论 对APL患儿跟踪检测PML RARα可早期发现分子复发 ,及时干预治疗可避免血液学复发。

Abstract:

Objective To study the significance of kinetic detection of the PML RARα fusion gene in the treatment of childhood acute promyelocytic leukemia (APL). Methods Ten children with APL were involved in this study. They were administered with all trans retinoic acid (ATRA) alone or with ATRA plus other chemotherapeutic drugs during remission induction, consolidation and maintenance treatments and were followed up. The bone marrow samples were regulary collected for morphological evaluation and PML RARα fusion gene detection (by RT PCR assay). Results The median follow up time was 42 months (ranging from 14 to 156 months). The estimated 5 year disease free survival rate was 56.0 ± 18.5% . Clinical complete remission (CR) was obtained in 9 cases (90%) and 1 case died on the 4th day after ATRA treatment. Of the 9 cases, 4 cases relapsed 14-42 months after CR and 5 cases remained continuous CR. Among the 4 cases with relapse, the PML RARα fusion gene was positive in 2 cases and it converted into positive in another 2 cases. Of the 5 cases with continuous CR, 3 cases with a positive PML RARα fusion gene 24, 42 and 36 months after CR were given salvage therapy. After the salvage treatment, the 3 cases had negative PML RARα fusion gene. Conclusions A continuous negative PML RARα fusion gene may be associated with long term disease free survival. The kinetic detection of PML RARα is important for modifying treatment and for preventing hematological relapse in the treatment of APL.