Study Of Factors Affecting The Occurrence And Lymph Node Metastasis Of Papillary Thyroid Microcarcinoma

ObjectiveTo observe the expression of CD56,CyclinD1and C-met in thepapillary thyroid microcarcinoma (PTMC) and paraneoplastictissue, explore the relationship between the occurrence of PTMCand lymph node metastasis， and analyze clinicopathologicalfeatures of PTMC.MethodsCollected and retrospectively analyzed clinical andpathological data of59cases of thyroid patients,who haveaccepted the thyroid surgery and diagnosed as PTMC in theChina-Japan Union Hospital of Jilin University from2010to2011.We divided these cases into2groups based on themetastasis status of the neck lymph nodes: lymph nodemetastasis group of30patients；lymph node metastasis absentgroup of29patients.Immunohistochemical method(SP) was used to detect the proteinexpression of CD56,CyclinD1and the C-met in PTMC andparaneoplastic tissues of two groups.Differences of various protein expression in PTMC and paraneoplastic tissues, and therelationship of various clinicopathological features of PTMCwere analyzed with SPSS13.0statistical software and valueof Ρ＜0.05for the difference was considered statisticallysignificant.Results1. The comparision of CD56protein expression in the PTMC andadjacent thyroid tissues: firstly, semi-quantitative scores ofCD56protein expression in the adjacent noncancerous thyroidtissues were significantly higher than that in the cancertissues in all cases(Ρ＜0.005); Furthermore,CD56expressionhad no difference in lymph node metastasis group and nonemetastasis group(Ρ﹥0.05).2.The expression scores of CyclinD1protein in PTMC tissueswere significantly higher than that in the adjcent tissues inall cases(Ρ＜0.005). Furthermore,the scores of the CyclinD1protein expressed in cancer tissues of lymph node metastasisgroup were lower than those without metastasis group,and thedifference was statistically significant(Ρ＜0.05）.3. The comparision of C-met protein expression in the PTMC andadjacent thyroid tissue:firstly, C-met protein expressionscores in the cancer tissues were significantly higher than that in the adjacent noncancerous thyroid tissues in allcases(Ρ＜0.005). Furthermore,the scores of the C-met proteinexpressed in cancer tissues of lymph node metastasis group werehigher than those in without metastasis group,but thedifference was not statistically significant(Ρ﹥0.05）.Inaddition,the expression of CyclinD1and C-met was positivelycorrelated by linear correlation analysis (r=0.66,Ρ＜0.05).4. Clinicolopathological analysis of PTMC: Firstly, we foundthat lymph node metastasis more easily occurred in patients ageless than45years old (Ρ＜0.05) or female patients (Ρ＜0.05),even more common in female patients with age under45years old(P<0.05with each single factor).In addition, there was nosignificant correlation between the lymph node metastasis ofPTMC and other clinicopathological features such as the cancersize,or histologic features (Ρ＞0.05).Conclusion1. The positive expression of CD56in adjacent noncanceroustissue and negative or weak expression in PTMC tissues,suggesting that there was a correlation between the lossexpression of CD56and the occurrence of PTMC.2. Positive expression scores of CyclinD1and C-met in cancertissues were significantly higher than that in adjacent noncancer tissues in all cases, implying that C-met andCyclinD1proteins were possibly indicators of the occurrenceof PTMC.3. The scores of the CyclinD1protein expressed in cancertissues of lymph node metastasis group were lower than thosein without metastasis group, suggesting that CyclinD1possiblyexercised negative regulatory effect on the occurrence of lymphnode metastasis of PTMC.4. By analyzing clinicopathological data of PTMC cases, wefound that the metastasis of PTMC was more easily occurred infemale patients or patients with age under45years old, evenmore common in female patients with age under45years old,suggesting that the people mentioned above should accept moreattention on general thyroid examination.