食管癌放疗患者外周血CK19 mRNA检测的临床意义

Clinical significance of CK19 mRNA detection in peripheral blood of esophageal cancer patients treated with radiotherapy

背景与目的肿瘤细胞在侵袭转移的早期阶段就可能进入血液循环,本研究检测食管癌根治性放疗前后外周血中循环肿瘤细胞(circulating tumor cells,CTC)标记细胞角蛋白19(Cytokeratin 19,CK19)mRNA的表达,探讨其临床意义。方法收集72例食管癌患者根治性放疗前后外周血,应用巢式RT-PCR检测CK19 mRNA的表达,分析其与临床病理特征及两年无进展生存(progerssion-free survival,PFS)的关系。结果放疗前后CK19 mRNA阳性者分别占44.4%(32/72)与30.6%(22/72),差别无统计学意义(P=0.085)。放疗前后CK19 mRNA阳性与淋巴结转移相关(P值分别为0.037和0.031)。生存分析也表明放疗前后CK19 mRNA阳性与不良PFS有关(P值分别为0.040和<0.001),Cox回归模型则进一步证实放疗后CK19 mRNA阳性是独立预后指标。结论放疗后外周血CK19 mRNA阳性可望成为食管癌根治性放疗预后判断的有效分子标记。

Objective Cancer cells may diffuse into the blood in their early stage of invasion and metastasis. We de- tected the marker of circulating tumor cells （CTC）, cytokeratin 19 （CK19） expression in peripheral blood of esophageal cancer patients treated with radiotherapy and evaluated its clinical significance. Methods CK19 mRNA expression was determined using nest RT-PCR in pre- and post-radiotherapy peripheral blood of 72 esophageal cancer patients, its associa- tions with clinicopathological features and 2-year progression-free survival （PFS） were further analyzed. Results The positive expression of CK19 mRNA in pre- and post-radiotherapy were 44. 4% （32/72） and 30. 6% （22/72）, respec- tively, the difference was not statistically significant （ P -- 0. 085）. Furthermore, CK19 mRNA expression was associated with lymph metastasis both in pre- and post-radiotherapy （P = 0. 037 and P = 0. 031 ）. Kaplan-Meier analysis also showed CK19 mRNA expression predicted adverse 2-year PFS both in pre- and post-radiotherapy （ P = 0. 040 and P 〈 0. 001 ）. However, Cox proportional hazard models indicated that only post-radiotherapy CK19 mRNA expression was an independent prognostic factor for esophageal cancer. Conclusion Post-radiotherapy CK19 mRNA expression maybe a useful biomarker related to poor prognosis in esophageal cancer patients treated with radiotherapy.