小儿CD56~+急性髓系白血病临床生物学特征

目的研究CD56+小儿急性髓细胞白血病(AML)的生物学特征及临床意义。方法对80例初治小儿AML进行细胞形态学、免疫表型、多药耐药P糖蛋白(P170)检测、临床观察、并常规采用HAE方案诱导治疗,判定疗效。结果综合我中心8年间小儿急性髓系白血病资料分析,CD56阳性率20.69%(30145)。CD56+患儿在FAB分型中以M2b、M5、M7多见,CD56+组中免疫表型特征为多表达CD34(85.00%和44.11%P=0.01)。HLA-DR(76.66%和42.00%P=0.003)。和PgP(85.71%和25.58%P=0.001)。此外,CD56+AML患儿髓外浸润现象明显(77.27%和45.00%P=0.017),尤其是淋巴结(59.09%和22.50%P=0.006)和脾脏(63.63%和22.50%P=0.002)受累显著,CD56表达与年龄、性别、白细胞计数、血红蛋白含量、血小板计数、及外周血幼稚细胞数无关,也不影响CR率和无病生存时间(DFS),但达首次缓解时间较长,中位时间56天。结论CD56+AML具有独特的临床生物学特征,生物学侵袭性较强,多表达耐药蛋白P170,预后较差。建议初诊时监测CD56分子表达以判断预后。

The biological and clinical significance of CD56 + antigen expression in child acute myeloid leukemia

Objective To study clinical characterisitics and therapeutic effects on CD56+ child acute myeloid leukemia (CD56+AML). Methods Morphology、immunophentype、 p-glycoprotein were examined in 80 previously untreated AML patients. Chemotherapeutic regimen HAE was used for the treatment. Results In child patients with de novo AML diagnosed and treated at our institution during an 8-year period, we found CD56 positivity 30 in 145 of patients. (20.69%). Where it has been associated with M_2b、M_5、 and M_7. These patients with CD56+ AML showed higher frequency of CD34(85.00% and 44.% P=0.01), HLA-DR(77.66% and 42.00% P=0.003). and the multidrug resistance (MDR)protein P (PgP), (85.71% and 25.58% P=0.001). In addition, we observed a significantly higher proportion of extramedullary involvement(77.27% and 45.00% P=0.017)including lymphnode (59.09% and 22.50% P=0.006)or splenic (63.63% and 22.50% P=0.002)involvement at diagnosis CD56 positivity did not correlate with age, sex wbc, Hb, Plt, blast, count, nor did it influence the outcome in terms of complete remission rate and disease-free survival(DFS). But CD56+AML achieved complete remission with a median time to CR of 56 days(P=0.003).Conclusion CD56+ AML might cousituts a distinct bioloigic and clinical disease entity. Our data showed that CD56 positivity at diagnoses associated with biological aggressiveness and overexpression of PgP. We suggest the evaluation of CD56 in all patients with acute leukemias at the time of diagnosis in view of poor dinical outcome.