大肠脱落细胞及其核DNA含量分析在大肠癌诊断中的意义

Colorectal Exfoliated Cell in Stool and Its Nuclear DNA Quantitative Analysis for Diagnosis of Colorectal Cancer

背景及目的:粪便中脱落细胞及其核DNA含量的检测有可能成为大肠癌筛查及早期诊断的无创途径。本文旨在了解脱落细胞及核DNA检测在大肠癌诊断中的意义。方法:1.粪便中脱落细胞学检测大肠腺癌患者46例,非大肠癌133例,同时进行粪免疫隐血试验(FOBT)。脱落细胞的提取参考Iyengar建立的离心淘洗法并加以改进。2.粪便中脱落细胞DNA含量分析包括33例大肠腺癌患者及30例对照者,利用图像分析仪测定脱落细胞核的DNA含量、核面积、核异形指数及≥5倍体细胞百分率。结果:1.粪便中脱落细胞对大肠癌检测的敏感性达76.09%,其敏感性与癌组织的部位、肿瘤大小、形态、Dukes分期、组织分化、淋巴结转移均无相关性(P>0.05)。粪便中脱落细胞及FOBT对大肠癌检测的敏感性间无显著性差异(76.09%vs84.78%,P>0.05),但脱落细胞及FOBT的特异性间存在显著性差异(98.50%vs73.68%,P<0.05)。2.脱落细胞核DNA定量分析中:脱落细胞核DNA含量、核面积、核异形指数、≥5C细胞百分率在癌组与非癌组间均存在差异显著性(P<0.05)。≥5C细胞百分率与癌组织不同分化程度间存在显著性差异(P<0.05)。结论:1.粪便中脱落细胞形态学检测对大肠癌的临床诊断具有重要意义;有望与FOBT序贯进行大肠癌的筛查,成为大肠癌早期诊断的无创途径。2.粪便中脱落细胞?

Background and Objectives:Detection of colorectal exfoliated epithelial cells and their nuclear DNA content may provide another non-invasive way of screening and early diagnosis of colorectal cancer.This stu dy was designed to analyze the roles of exfoliated cells in stool and its nuclear DNA conte nt in diagnosis of colorectal cancer.Methods :1.One hundred and seventy nine indiv iduals were selected,forty-six of t hem had pathological confirmation o f colorectal carcinoma.The other 133persons had no colonoscopic evidence of colorec tal malignancy and therefore served as control.Exfoliated cells in the stool were is olated by elutriation,and the elutr iation means was modified Iyengars method.All individuals in the study had stool sp ecimens for occult blood test(FOBT).2.Nuclear DNA content and morphome tric quantitative analysis in the exfoliated cells was performed on the 33patients with colorectal cancer and 30i ndividuals served as control.The parameters selected in this study were DNA content,nucle ar area,nuclear irregular index,an d percent of≥5C cells.Results:1Exfoliative cytology and FOBT:In 35of 46cases of colorectal magligancy(76.09%),cytology was positive:5cases demonstrated dysp lastic cells,4cases indicated susp ected carcinoma cells,26cases show ed carcinoma cells.The positive rate of exfoliated cells had no significant relation to locations,sizes,histo morphologies,histological differentiations,Dukes stages,an d lymph node metastases of the lesion(P>0.05).Exfoliative cytology had a 98.50%(131/133)specificity for colorectal cancer i n the study.The sensitivity for colorectal cancer was no significant difference between the two methods of exfoliative cyto logy and FOBT(76.09%vs 84.78%,P>0.05),but the specificity for colorectal cancer,exfoliative cytology was significant higher than FOBT(98.50%vs 73.68%,P<0.05).2.DNA analysis of exfoliated cells nuclear,DNA content,nuclear area,nuclear irregular index and percent of≥5C cells in the stool were significan t higher in colorectal cancer than in control group(P<0.05).The percentage of≥5C cells were significantly asscoia ted with histological grade(P<0.05).Conclusions :1.Detection of exfoliated cells in s tool plays an important role in diagn osis of colorectal cancer.Testing of FOBT and exfoliated cells sequentially hopes to be a new useful non-invasive test for screening of c olorectal cancer.2.DNA analysis of exfoliate d cell in stool may provide an objecti ve method of determining malignant g rades and diagnosis of colorectal cancer.