胃癌前病变MC5抗原定量分析及对胃癌高危人群预测价值的探讨

The Prediciting Value of MC5Ag in Conceration of Dysplasia of Gastric Mucosa

应用本院制备的抗结肠癌单克隆抗体ＭＣ５及ＡＢＣ免疫组化染色，检测了６４例具有随访结果的胃粘膜异型增生标本。用计算机图像分析系统对ＭＣ５抗原的表达进行了定量分析，并通过计算约登指数及绘制ＲＯＣ曲线探讨了高危界值。６４例标本中包括癌变组３０例，未癌变组３４例，随访时间６～７２个月（平均２６个月）。免疫组化染色结果显示，癌变组３０例标本中有２０例表达阳性（６６．７％），未癌变组３４例标本中仅８例呈阳性表达（２３．５％），两组比较差异显著（Ｐ＜０．０１）。图像分析等结果显示，ＭＣ５的平均灰度值＞０．２２为高危界值，以此值作为判定不典型增生是否具有癌变倾向的依据，其灵敏度为７６．７％，特异度为７３．５％，准确度为７５．０％。结论：ＭＣ５抗原的表达程度和胃粘膜不典型增生癌变关系密切。ＭＣ５抗原表达阳性的胃粘膜不典型增生尤其当灰度值≥０．２２的病例，是具有潜在癌变倾向的高危人群，对这些病人进行严密的随访监测，可提高早期胃癌的检出率。

To access the predicting value of MC5Ag in canceration of dysplasia of gastric mucosa, we studied the expression of MC5Ag in 64 cases of gastric mucosa with dysplasia, which had been followed up, by using ABC immunohistochemical methd Furthermore, quantitative detection of MC5Ag was taken by computer aided image analysis, and the cut off value of high risk of MC5g in dysplasia was also carried out through operating Youden′s Index(YI) and drawing receiver operation characteristic (ROC) curve The result of immunohistochemical staining was that the expression of MC5Ag was found in 20 out of 30 cases with canceration, but only in 8 out of 34 cases with no canceration The difference between the two groups was statistically significant(P<0 01) The quantitative computer aided image analysis of MC5Ag showed that the cut off value of high risk of MC5Ag in gastric dysplasia was 0 22 With the density of MC5Ag 0 22 as criterion of canceration probability, the sensitivity was 75 74%, the specificity was 73 0%, the accuracy was 75 0% Conclusion: the expression of MC5Ag may be a good marker to distingnish if the dysplasia of gastric mucosa has tendence of cancerization If a close following up was performed in these patients (particular density>0 22), it may be possible to detect early gastric cancer