分类检测非小细胞肺癌患者外周血中循环肿瘤细胞的临床价值

Clinical value of classified detection of circulating tumor cells in peripheral blood of NSCLC patients

目的：探讨利用上皮细胞黏附分子（ EpCAM）分类检测非小细胞肺癌（ NSCLC）患者外周血中循环肿瘤细胞（CTCs）的临床意义。方法收集47例NSCLC患者的外周血样品各7．5 ml，其中3例患者在每一治疗周期结束时采集外周血样品用于动态监测CTCs。以阴性？磁性法分离和富集CTCs，经EpCAM和CK 7／8免疫荧光染色后，流式细胞仪鉴定CTCs并计数。结果47例患者的血液样品中，表达EpCAM的CTCs检出率为48．9％（23／47），其中Ⅰ～Ⅱ期、Ⅲ期和Ⅳ期患者的检出率分别为64．3％（9／14）、40．0％（4／10）和43．5％（10／23）。不表达EpCAM的CTCs检出率为87．2％（41／47），其中Ⅰ～Ⅱ期、Ⅲ期和Ⅳ期患者的检出率分别为78．6％（11／14）、90．0％（9／10）和91．3％（21／23）。两类CTCs的总检出率差异有统计学意义（P＜0．001），其中Ⅰ～Ⅱ期和Ⅲ期患者的两类CTCs的检出率差异均无统计学意义（均P＞0．05），而Ⅳ期患者的两类CTCs检出率差异有统计学意义（P＝0．001）。各分期患者外周血中，不表达 EpCAM 的 CTCs 数量均明显高于表达 EpCAM 的 CTCs 数量（均 P＜0．05）。Ⅳ期患者中，不表达EpCAM的CTCs＞90％患者的比例明显高于Ⅰ～Ⅱ期患者（P＝0．030），不表达EpCAM的CTCs在50％～90％患者的比例明显低于Ⅰ～Ⅱ期患者（P＝0．001）。不表达EpCAM的CTCs＞50％时，患者的治疗普遍无效（ P＝0．033）。结论 EpCAM 分类检测 CTCs，有助于评估NSCLC患者的远处转移和治疗疗效。

Objective To investigate the clinical value of detection of circulating tumor cells （ CTCs） classified by epithelial cell adhesion molecule （ EpCAM） in peripheral blood of patients with non？small cell lung cancer （NSCLC）. Methods Peripheral blood samples （7.5 ml each time） were collected from 47 NSCLC patients. Among them, blood samples were collected at the end of each therapy-cycle in three patients for longitudinal monitoring of CTCs. CTCs were enriched by the depletion of leucocytes using a magnetic bead separation technique, stained with EpCAM, cytokeratin 7/8 and their isotypic control antibodies, respectively, and then identified and counted by multi-parameter flow cytometry. Results In the blood samples from 47 patients, EpCAM-positive CTCs were detected in 64.3%（9/14）, 40.0%（4/10） and 43.5%（10/23） of patients in stages Ⅰ-Ⅱ,Ⅲ and Ⅳ, respectively. EpCAM-negative CTCs were detected in 78. 6%（ 11/14 ） , 90. 0%（ 9/10 ） and 91. 3%（ 21/23 ） of patients in stage Ⅰ-Ⅱ, Ⅲ, and Ⅳ, respectively. The total detection rates of EpCAM-positive and EpCAM？negative CTCs were 48.9%（23/47） and 87.2%（41/47）, respectively, showing a statistically significant difference between them （P〈0.001）. According to the stage of the cancer, there was a significant difference between the detection rates of the two types of CTCs in patients of stageⅣ（ P=0.001） , but not in stageⅠ-ⅡandⅢ（ P〈0.05） . The number of EpCAM-negative CTCs was significantly higher than that of EpCAM-positive CTCs in all stages （P〈0.05）. The frequency of patients with the percentage of EpCAM-negative CTCs 〈90% was significantly higher in stage Ⅳ patients than that in stage Ⅰ-Ⅱ cases （P=0.030）, while the frequency of patients with the percentage of EpCAM-negative CTCs between 50%-90% was significantly lower in the stageⅣthan that in the stage Ⅰ-Ⅱ patients （P=0.001）. The treatment of most patients with EpCAM-negative CTCs〈50%showed to be ineffective （P=0.033）. Conclusion Detection of CTCs classified by EpCAM in peripheral blood is helpful in evaluating the distant metastasis and treatment effectiveness of NSCLC patients.