荧光定量PCR对N0期结直肠癌淋巴结微转移的检测及其临床意义

Detection of Micrometastasis and Its Clinical Significance in Lymph Nodes from N0 Colorectal Cancers by FQ-PCR

目的探讨N0期大肠癌淋巴结微转移的检测及其临床意义。方法采用荧光定量聚合酶链反应(FQ-PCR)检测45例行根治术的N0期大肠癌患者的453枚淋巴结中细胞角蛋白20(cytokeratin,CK20)mRNA的表达以检出微转移。结果45例N0期大肠癌病人的453枚淋巴结中,有20例(44.4%)共46枚(10.2%)淋巴结检出微转移。微转移与患者年龄、性别、肿瘤大小、分化程度等无关,但与肿瘤浸润深度相关(χ2=5.445,P<0.05)。20例微转移患者与25例无微转移患者平均随访时间分别为19.6和21.4月。20例微转移患者中7例发生复发转移,5例死亡;而无微转移25例中仅1例因复发转移而死亡(χ2=7.305,P<0.05)。有微转移组和无微转移组的生存率分别是75.0%(15/20)和96.0%(24/25),两组患者之间差异有统计学意义(χ2=4.240,P<0.05)。结论CK20mRNA的FQ-PCR是检测N0期大肠癌淋巴结微转移灵敏而特异的方法,可对精确临床分期、判断患者预后及制定合理的治疗方案提供一定的理论依据。

Objective To study the detection of lymph node micrometastasis in N0 colorectal cancer patients and its clinical significance in these patients. Methods In the study, 453 lymph nodes obtained from 45cases of NO colorectal cancer going curative operation were examined, using fluorescent quantity polymerase chain reaction （FQ-PCR） assay to detect cytokeratin 20 （CK20） mRNA expression for identifying micrometastasis. Results Micrometastasis was detected in 46 lymph nodes （ 10. 2%, 46/453） of 20 cases （44. 4% ,20/45）. The presence of micrometastasis was correlated with invasion depth of primary tumor, but was not related to sex, age, size and differentiation of primary tumor. The mean follow-up time in the positive groups （20 cases） with micrometastasis and the negative groups（25 cases） without micrometastasis were 19. 6 and 22.4 months respectively, but there were 7 cases post-operative recurrence, metastases and 5 cases died in positive groups （20 cases） with micrometastasis, only 1 case died because of recurrence or metastases in negative groups （25 cases） without micrometastasis （X^2 = 7. 305, P〈0. 05）. The disease-free survival of positive and negative groups was 75.0% （15/20） and 96. 0% （24/25）, respectively. The two groups have significant difference （ X^2 = 4. 240, P〈 （0.05）. Conclusion CK20 FQ-PCR assay is a sensitive and specific method to detect lymph node micrometastasis in the patients with NO colorectal cancer. The detection of CK20 mRNA in lymph nodes may contribute to improve the accuracy of clinical staging, determine patient＇s prognosis and provide information for rational adjuvant therapy.