The Expressing And Significance Of C-kit And PTEN In Thymic Epithelial Tumors

Background:So many reasons for thymic epithelial tumors such as slow progression and low incidence,pathological type complex,many classification methods,both under the microscope the complex structure and contradiction of pathology and prognosis,few prospective randomized controlled clinical experimental research,lead clinicians lack of knowledge of thymoma.It is a fact that there is controversial about reasonable pathological classification and treatment modalities.Objective: To study the expression of c-kit,PTEN in thymoma and to explore the relationship between the expression of c-kit,PTEN and the thymoma status,including the pathological types,clinical stage and MG combine.Methods: Surgically resected and pathologically proved cases of thymic hyperplasia,thymoma and thymic carcinoma were collected.All the patients received neither radiotherapy nor chemotherapy before the surgery.Record pathological type,clinical stage and whether combined with MG in patients with thymic epithelial tumors.Thymus hyperplasia in 14 cases,60 cases of thymoma and 12 cases of thymic carcinoma resection specimens of routinely paraffin-embedded tissues were collected.The expression of c-kit and PTEN were detected by immunohistochemistry S-P method.All the results were statistically analyzed with SPSS 19.0 software package.Results:1 The positive rates of c-kit protein was gradually increased in thymic hyperplasia,thymoma and thymic carcinoma were 7.1%,13.3%,66.7%,and there was statistical difference among the three groups(P <0.05);The positive rates of c-kit were 9.4% in tissues of noninvasive thymoma(A+AB),which were lower than the rates of 17.9% in invasive thymoma(B1+B2+B3)(P =0.335);The positive rates of c-kit protein in Masaoka clinical stage Ⅰ,Ⅱ,Ⅲ,Ⅳ were 12.5%、13.3%、15.4%、12.5%,and there were no statistical difference among the four groups(P =0.998);The positive rates of DKK1 were 13.5% in tissues of thymoma with MG,13.0% in tissues of thymoma without MG,there were no statistical difference between the two groups(P =0.985).2 The positive rates of PTEN protein was gradually decreased in thymic hyperplasia,thymoma and thymic carcinoma were 85.7%、55.0%、16.7%,and there was statistical difference among the three groups(P <0.05);The positive rates of PTEN were 71.9% in tissues of noninvasive thymoma(A+AB),which were significantly lower than the rates of 35.7% in invasive thymoma(P <0.05);The positive rates of Survivin protein was gradually decreased in Masaoka clinical stage Ⅰ,Ⅱ,Ⅲ and Ⅳwere 83.3%、53.3%、30.8%、12.5%,and there was statistical difference among the four groups(P <0.05);The positive rates of Survivin were 54.1% in tissues of thymoma with MG,60.9% in tissues of thymoma without MG,there were no statistical difference between the two groups(P =0.604).Conclusions:1 The expression of c-kit protein has positive correlation with pathological types of thymoma,but not with invasion,which indicating that the C-kit is a good molecular markers to identifythymoma and thymic carcinoma.We must do some further research to prove that whether it can be helpful in the diagnosis of invasive thymoma.2 The expression of PTEN has negative relationship with pathological types and Masaoka clinical stage.The PTEN not only will be helpful in judging the maligant degree,but also in providing important reference for the diagnosis of thymoma.3 The expression of c-kit and PTEN play a role in the occurrence and development of thymic epithelial tumors.Unite examining the c-kit and PTEN will be helpful to comprehensive evaluation and to guide treatment.But the expressions of c-kit and PTEN weren’t correlated with whether combined with MG.