中文摘要：

目的 评估血浆游离DNA含量在非小细胞肺癌（non-small cell lung cancer,NSCLC）诊疗中的应用价值。方法 收集61例非小细胞肺癌患者和18例健康人的血浆,提取血浆游离DNA,荧光定量PCR方法 检测DNA浓度。结果 健康人血浆游离DNA水平中位数为73.70（53.49~85.03）ng/ml,非小细胞肺癌患者血浆游离DNA水平为179.43（160.94~401.34）ng/ml,两者间差异有统计学意义（P〈0.01）。血浆游离DNA含量与非小细胞肺癌患者的性别、年龄、吸烟状况及病理类型均无明显相关性,与有无转移存在相关性（P〈0.01）。结论 非小细胞肺癌患者的血浆游离DNA是一种潜在有价值的生物学标志物,可作为临床上诊断肺癌、预测疾病进展、快速评估治疗疗效的工具。

英文摘要：

Objective To evaluate the dection of plasma cell free DNA content in the diagnosis and treatment of non-small cell lung cancer （NSCLC）. Methods The plasma samples were collected from 61 cases of NSCLC patients and 18 healthy subjects. The plasma cell free DNA was extracted using GIAGEN reagent. The concentration of cell free DNA was detected by fluorescence quantitative PCR method. Results The level of plasma cell free DNA was 73.70 （ 53.49 - 85.03 ） ng/ml in control group and 179.43 （ 160. 94 - 401.34 ） ng/ml in NSCLC group （ P 〈 0. 01 ）. Plasma cell free DNA was not correlated with gender, age, smoking and pathological type of NSCLC patients, but correlated with cancer metastasis （ P 〈 0. 01 ）. Conclusion The dection of plasma cell free DNA can be used as a biological marker for diagnose and prognosis for NSCLC patients.