Detection And Clinical Implication Of Aneuploidy Of Chromosomes2,3,11and20in Gastric Adenocarcinoma

Objectives:The aim of this study was to find out the value of chromosomes aneuploidy in early diagnosis and postoperative recurrence of gastric adenocarcinoma(GAC).Methods:Samples of tissues, including56GAC,39pericancerous mucosa and39normal gastric mucosa from the distant cutting margin, were obtained from56patients with gastric cancer who underwent surgical resection of their tumors between Oct,2009and Feb,2012. For FISH analysis, we selected four centromere probes, Cen2, Cen3, Cenll and Cen20specific for Chromosmoe2,3,11and20. Tumor samples were not used for this study when slides contained a low percentages (<30%) of tumor cells. Reviewed all cases’ HE slides and summarized the clinical and pathological data.Results:We found that Cen20(88.4%,80.6%) had the highest incidence of aneuploidy in both tumor and pericancerous mucosa. then followed by Cen3(85.7%,64.5%), Cenll (82.6%,57.6%) and Cen2(78.3%,43.3%). The aneuploidy of Cen11displayed significant correlation with Lauren’s claasification (p<0.05), and all diffuse-type adenocarcinoma exhibited chromosome aneuploidy. There also a significant correlation between pericancerous mucosa and gross classification (p<0.05). As pericancerous mucosa were classified as chronic inflammation, intestinal metaplasia and atypical hyperplasia, the aneuploidy ratio of atypical hyperplasia of Cen2, Cen3and Cenll (70.6%,94.1%,79%respectively) appeared much higer than chronic inflammation(11.1%,20.2%,40%respectively). Aneuploidy was more easier to be detected in normal gastric mucosa from the distant cutting margin appeared as atypical hyperplasia or obtained from poorly differentiated adenocarcinoma (especially signet ring cell carcinoma), and most frequent aneuploidy was found in Cen20, in which the ratio of chronic inflammation, intestinal metaplasia and atypical hyperplasia was12.5%、18.2%、50.0%respectively. All four chromosomal aneuploidies was statistically significant on different sample regions which were tumor, pericancerous mucosa and normal gastric mucosa from the distant cutting margin (p<0.05).Conclusions:We demonstrated more frequent chromosomal aneuploidy in gastric carcinomas than pericancerous mucosa. We also demonstrated the pattern of chromosomal alterations in paired pericancerous mucosa and carcinomas showed great similarity. In the normal gastric mucosa from the distant cutting margin, even most of chromosomes were diploid, the detection of chromosome aneuploidy still suggested the recurrence of postoperative gastric. Aneuploidy of Cen2, Cen3and Cenll and Cen20, especially Cen20, in pericancerous mucosa might be used as a candidate marker for the early diagnosis of gastric adenocarcinoma and might have a predictive role in postoperative recurrence.