早期T细胞前体急性淋巴细胞白血病(ETP-ALL)是一种罕见的T细胞白血病亚型,在表型上表达成熟的T细胞标记和未成熟的骨髓标记,如CD33。Gemtuzumabozogamicin(GO)是与细胞毒性剂加车霉素缀合的CD33分子靶向抗体的新型药物。GO预计对ETP-ALL有效。体内研究有望在细胞系中发挥抗白血病作用;然而,缺乏支持这项研究的临床报告.我们使用GO治疗患有CD33阳性ETP-ALL的患者。
■我们治疗了一名患有ETP-ALL的81岁男子。患者的白血病表达T细胞和髓样标志物,包括cyCD3,CD5,CD7,CD33和HLA-DR。最初,患者使用包括环磷酰胺在内的急性淋巴细胞白血病的标准化疗方案进行治疗,柔红霉素,长春新碱,l-天冬酰胺酶,和泼尼松龙。诱导化疗产生了预期的完全血液学反应;然而,骨髓母细胞仍然存在。巩固化疗后,患者维持完全的血液学反应。此后,我们将巩固方案改为奈拉滨,不能有效减少骨髓母细胞。经过两个疗程的奈拉滨治疗,在确认患者残余白血病细胞中CD33表达仍为阳性后,我们最终以每周8mg/m2的剂量使用了GO。GO治疗病人的白血病无效,和外周母细胞在治疗后30天增加。患者在开始GO治疗后81天死亡。
■这是GO对ETP-ALL产生负面影响的第一例临床病例。由于ETP-ALL的GO抗性机制尚未完全阐明,应考虑进行治疗修改以达到最佳临床疗效。
UNASSIGNED: Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) is a rare subtype of T-cell leukemia that phenotypically expresses mature T-cell markers and immature myeloid markers such as CD33. Gemtuzumab ozogamicin (GO) is a novel agent for the CD33 molecular targeting antibody conjugated to the cytotoxic agent calicheamicin. GO is anticipated to be effective against ETP-ALL. In vivo studies promise antileukemic effects in cell lines; however, clinical
reports to support this research are lacking. We treated a patient who suffered from CD33-positive ETP-ALL using GO.
UNASSIGNED: We treated an 81-year-old man who suffered from ETP-ALL. The patient\'s leukemia expressed T cell and myeloid markers including cyCD3, CD5, CD7, CD33, and HLA-DR. Initially, the patient was treated using a standard chemotherapy regimen for acute lymphoblastic leukemia comprising cyclophosphamide, daunorubicin, vincristine, l-asparaginase, and prednisolone. The induction chemotherapy produced the expected complete hematological response; however, bone marrow blasts remained. Following consolidation chemotherapy, the patient maintained a full hematological response. Thereafter, we changed the consolidation regimen to nelarabine, which did not reduce bone marrow blasts effectively. After two courses of nelarabine therapy, we finally used GO at an 8 mg/m2 weekly dose after confirming that CD33 expression was still positive in the patient\'s residual leukemic cells. GO was ineffective in treating the patient\'s leukemia, and peripheral blasts increased 30 days following treatment. The patient died 81 days after initiating GO therapy.
UNASSIGNED: This is the first clinical
case of GO having a negative impact on ETP-ALL. Because the GO resistance mechanism for ETP-ALL has not been fully elucidated, treatment modification should be considered to achieve optimal clinical efficacy.