Study On The Correlation Between Spiral CT Features And Expression Of Cyclooxygenase-2, Nm23 In Patients With Esophageal Carcinoma

Background and purpose: Esophageal carcinoma is common malignant tumors in our country. Considered as an effective method in examination of esophageal carcinoma, spiral CT (SCT) can provide with more important information of the tumor. Imaging features of all tumors are based on their pathological natures and are determined by their biological behaviors. Researches have demonstrated that multiple genes changes result in tumor genesis and progression. In the complicated courses, Cyclooxygenase-2(Cox-2) and nm23 are involved.Cox-2 is a rate-limiting enzyme in the process of compounding prostaglandin E₂ (PGE₂),and PGE₂ can result in carcinoma might by make mucosa proliferate and restrain immunity, so Cox-2 is considered as a carcinoma gene. Nm23, of which nm23-H1 might play the most important role, has the function of inhibiting tumor metastasis, especially has close correlation in lymph node metastasis,nm23 might be a gene maker in the prophecy of patients' prognosis.The inherent relationship between modern medical imaging and molecular biology can be found by comparing SCT features of tumor with its biological behaviors, it has been the focus of recent researching.The purpose of the study is to evaluate the correlation between SCT features, the expressions of Cox-2 and nm23 in esophageal carcinoma.Materials and methods: Spiral CT scans were preformed in 44 patients with esophageal carcinoma before operation, among them 25 patients add Spiral CT contrast--enhanced scans. About 10 minutes before the scanning, 15mg—20mg 654-2 was injected intramuscularly, then 800-1200ml lukewarm water was taken.Spiral CT examination was performed with a German SIEMENS Helical scanner and patients was lie supine. The field of scanning from lower neck, to upper abdomen. The collimation was 10ram, pitch 1:1, the collimation of tumor location was 5ram which was defined according to the barium meal examination or esophageal endoscope. Patients are asked to hold their breathing for 1 time. Contrast-enhanced scans contrast medium was (300mgI/ml) Ultravist or Omnipaque. 100ml of it was injected via cubital vein with the speed of 2.5ml/s—3ml/s, and the scanning began at 40s after the start of injection. After operation, all the specimens were fixed in 10% neutral formalin and embedded in paraffin. Immunohistochemical streptavidin peroxidase conjugate method was used to analyze the expressions of Cox-2 and nm23 in esophageal carcinoma. Statistical analysis was performed with SPSS 12.0 software, using Chi-square and test and Kappa test. Statistically significant level was considered as "alpha equals 0.05".Results: 1.Compared with operation and pathology, the accuracy of Spiral CT scan in judging adjacent-infiltration and lymph node metastasis in 44patients was 88.6%(39 of 44) and (40 of 44); The diagnostic outcome of Spiral CT in judging adjacent-infiltration and lymph node metastasis had good coincidence with operation and pathology (Kappa was 0.758 and 0.811).2. The correlation between Cox-2 expression and SCT features in esophageal carcinoma: The Cox-2 positive rate was 79.5% (35 of 44).â‘ In the group that tumor size>5cm and the group that tumor size≤5mm in SCT features, the positive rates of Cox-2 gene protein were 95.2% (20 of 21) and 65.2% (15 of 23), witch had statistically significant between two groups(x²=6.080,P=0.023). â‘¡In the adjacent-infiltration group and the non-adjacent-infiltration group in SCT features, the positive rate of Cox-2 gene protein were 100.0% (16 of 16) and 67.9 (19 of 28) respectively. Which had statistically significant between two groups (x²=6.465,P=0.016).â‘¢In the group with lymph node metastasis and the group without lymph node metastasis in SCT features,the positive rates of Cox-2 were 94.4% (17 of 18) and 69.2% (18 of 26) respectively and there was statistically significant (x²=4.156, p=O.044).â‘£In the group which depth of invasion T3+T4 and T1+T2 in SCT features, the positive rates of Cox-2 were 92.0% (23 of 25) and 63.2% (12 of 19) respectively and there was statistically significant (x²=5.519, P=0.024).⑤The positive expression of Cox-2 gene protein were not closely related with the tumor position, gross morphology in esophageal cancer patients(P>0.05).3. The correlation between nm23 expression and SCT features in esophageal carcinoma: In 44 cases, the nm23 positive rate was 68.2%(30 of 44).â‘ In the group with lymph node metastasis and the group without lymph node metastasis in SCT features. The positive rates of nm23 were 44.4%(8 of 18)and 84.6(22 of 26) respectively and there was statistically significant (x²=7.912,P=O.OO8).â‘¡In the group with depth of invasion T1+T2 and T3+T4 in SCT features the positive rates of nm23 were 89.5% (17 of 19) and 52.0%(13 of 25) respectively and there was statistically significant (x²=6.988, p=0.008).â‘¢The positive expression of nm23 gene protein were not closely related with the tumor position, gross morphology and tumor size in esophageal cancer patients (p＞0.05)4. The correlation of Cox-2 and nm23 expression with lymph node metastasis in esophageal carcinoma: Combine the two gene protein all abnormal expression to one group (A group ) which Cox-2 was over expression and mean while nm23 was low-expression; combine the two gene protein all normal expression or only one abnormal expression to one group (B group). Compare the two group in lymph node metastasis (LNM). The LNM rates of A group were 69.2% (9 of 13), the LNM rates of B group were 29.0% (9 of 31) and there was statistically significant (x²=6.123,p=0.016).Conclusions:1.SCT scan was a valuably diagnostic technique for the patients of esophageal carcinoma before therapy.2.The positively expression of Cox-2 protein was positively related to tumor size. adjacent-infiltration, infiltration depth and lymph node metastasis of SCT feature, which indicates that may promote infiltration and metastasis of esophageal carcinoma.3.The positively expression of nm23 protein was negatively related to lymph node metastasis and infiltration depth of SCT feature, which are important prognostic markers in esophageal carcinoma.4.The abnormal expression of Cox-2 and nm23 protein may act on the lymph node metastasis of esophageal carcinoma together.5.The adjacent infiltration lymph node metastasis and depth of invasion of esophageal carcinoma can be judged by analyzing SCT features and the expression of Cox-2 and nm23 protein together, which may help for choosing the optimal method in patient's therapy.