Di Bona Eros, Sartori Roberto, Zambello Renato, Guercini Nicola, Madeo Domenico, Rodeghiero Francesco
Department of Cellular Therapy and Hematology, Division of Hematology, San Bartolo Hospital, Vicenza, Italy.
Haematologica. 2002 Mar;87(3):250-6.
CD56 antigen expression has been reported in several hematologic malignancies. In acute myeloid leukemia (AML)M2 with t(8;21) and acute promyelocytic leukemia (APL) it has been found to be consistently associated with an unfavorable prognosis, whereas in other AML subtypes its role remains uncertain. We investigated CD56 expression in a cohort of AML patients in order to assess its frequency and prognostic relevance.
Immunophenotypic analysis including that of CD56 antigen was available for 171 consecutive AML patients (139 with AML and 32 with APL), enrolled between December 1995 and December 1999 at a single institution. A sample of fresh bone marrow cells taken at diagnosis was recorded as positive when at least 20% of the cells double-stained with specific monoclonal antibodies against CD56 and CD33 antigens.
CD56 positivity was demonstrated in 37 cases (21.6%). Its frequency was lower in M4 (6%) and higher in M5 (37%). The median percentage for CD56+ blasts was 56% (range 21-99%). CD56 positivity did not correlate with age, sex, blast count, favorable or unfavorable cytogenetics at diagnosis, nor did it influence the outcome in terms of complete remission (CR) duration (606 vs. 417 days, p=n.s.) or overall survival (OS) (210 vs. 277 days, p= n.s.). In the APL subgroup a significant difference in relapse rate was found at 3 years (71.4% in the CD56 positive group vs. 12% in the CD56 negative group, p=0.005).
Our data confirm that CD56 positivity in APL patients at diagnosis is associated with a worse prognosis, suggesting that close molecular monitoring is necessary in CD56 positive APL patients. In contrast, the prognostic role of CD56 remains uncertain in the other AML subtypes.
已有报道称CD56抗原在多种血液系统恶性肿瘤中表达。在伴有t(8;21)的急性髓系白血病（AML）M2和急性早幼粒细胞白血病（APL）中，发现其与不良预后始终相关，而在其他AML亚型中，其作用仍不确定。我们调查了一组AML患者的CD56表达情况，以评估其频率及预后相关性。
1995年12月至1999年12月期间，在一家机构连续纳入了171例AML患者（139例AML和32例APL），对其进行了包括CD56抗原在内的免疫表型分析。当至少20%的细胞与抗CD56和CD33抗原的特异性单克隆抗体双染时，诊断时采集的新鲜骨髓细胞样本记录为阳性。
37例（21.6%）患者显示CD56阳性。其频率在M4中较低（6%），在M5中较高（37%）。CD56+原始细胞的中位百分比为56%（范围21 - 99%）。CD56阳性与年龄、性别、原始细胞计数、诊断时的有利或不利细胞遗传学均无相关性，在完全缓解（CR）持续时间（606天对417天，p =无显著性差异）或总生存期（OS）（210天对277天，p =无显著性差异）方面也未影响结局。在APL亚组中，3年时复发率存在显著差异（CD56阳性组为71.4%，CD56阴性组为12%，p = 0.005）。
我们的数据证实，诊断时APL患者的CD56阳性与较差的预后相关，提示对CD56阳性的APL患者进行密切分子监测是必要的。相比之下，CD56在其他AML亚型中的预后作用仍不确定。
