A Preliminary Correlative Study Of CT Presentation With Histo-differentiation And P53,Ki67 Expression In Gastric Cancer

With the original image and postprocessing image complementing each other, Multi-slice spiral computed tomography (MSCT) can manifest the position, show the mucous information and the relationship between the tumor and the surrounding structures, and sometimes show the blood-supplied vessels. Even more MSCT can discover the lymph nodes and the visceral metastasis. ALL of above make MSCT a kind of very helpful and reliable examination. TNM staging of the gastric cancer is becoming more and more interested study rentent years. But there is few report about relationship between spiral CT findings and histological differentiation.p53 as the most changeble tumor gene, is the most hot and most interested protein, and until now there is still not a received conclusion between the expression of p53 and CT findings. There is no credible report about CT findings and expression of Ki67, which is very important protein showing the ability of proliferation in gastric carcinoma.Objective:To study the relationship between spiral CT findings and histological differentiation,expression of p53 and Ki67 in gastric carcinoma, to improve diagnostic value of Multi-slices spiral computed tomography scans in gastric carcinoma evaluation before operation and show more information for clinic.Materials and Methods:Triphasic spiral CT scans were performed in 158 patients (110 men and 48 women; range of age, 21-84 years; mean age, 60 years) who has been pathologically proved gastric carcinoma from March 2008 to February 2009. All CT findings were obtained with a sixteen-channel multi–detector row CT scanner (LightSpeed; General Electric Medical System). X-ray tube voltage, tube current, and gantry rotation time for all scans were 120 kV, 360 mA, and 0.8 second per rotation respectively. All the subjects fasted 4-6 hours, injected 654-2 20 mg, the venous channel was established through the antecubital vein, non-iodic ion contrast agent ultavist or omnipaque, whose iodine content is 300mg/l, was injected by automatic high pressure injector with speed of 3ml/s and total dose of 100ml. after that we collected the data of arterial phase,venous phase and balance phase at 20-25s,25-35s,55-60s, all the phases scope included stomach except for the balance phase arrange from diaphragmatic dome to the cavitas pelvis using 5mm as slice thick 5mm as slice distance. Reconstructed with 1.25mm thickness and intermission, with the standard reconstruction. Then sent to the workstation (ADW4.2). Selected the venous phase to reconstruct, with the methods of MPR respectively. Two blinded reviewers independently studied CT findings (included maximal diameter and thickness of tumor in three dimensional picture of CT image, enhanced features and degree of enhancement, thickness of peri-tumor-density band, the muscous situation,the lymph nodes and the visceral metastasis.) by using original image and post-processing image . All the Patients were operated in a week after the CT examination. All the tumors specimen were collected. The expression of p53 and Ki67 were detected with immunohistochemistry and reverse transeription Polymerase chain reaction(RT-PCR). All above CT findings compared with histological differentiation and expression of p53 and Ki67. Statistically analysis was performed with SPSS software package.Results: All the observe indexes had been observed well and recorded and the correlation was found between enhanced characteristics of gastric carcinoma and its histological differentiation and expression of p53 and Ki67:1,111 lower differentiated and 47 high/moderately differentiated in 158 patients. Thickness of tumor in three dimensional picture of CT image were significantly correlated with tumor histological differentiation(χ2=5.554, p=0.018), but maximal diameter in three dimensional picture of CT image not so correlated with it (χ2=2.054, p=0.152); the enhanced features (χ2=5.273, p=0.022)and degree of enhancement(χ2=4.978, p=0.026) and thickness of peritu-tumor-density band (χ2=8.664, p=0.003)were significantly correlated with tumor histological differentiation; lymph nodes metastasis was correlated with histological differentiation, which not correlated with the the muscous situation and the visceral metastasis at same time. 2,Positive expression of p53 take 65.2%, negative expression take 34.8%. Lymph nodes metastasis was correlated with expression of p53 (P<0.05), and others showed no significantly correlation. 3,Positive expression of Ki67 take 75.9%, negative expression take 24.1%. Thickness of tumor in three dimensional picture (χ2=5.674, p=0.017), lymph nodes metastasis (χ2=5.028, p=0.025) and enhanced features of enhancement (χ2=10.455, p=0.001) were correlated with expression of Ki67.Conclusion:Multi-slice computed tomography scanning as a kind of convenient and painless examination can initially show tological differentiation of gastric cancer and expression of p53,Ki67 before the operation, also help to look into pathologic and molecular level, so evaluate recrudescence,infiltrating metastasis and prognosis. MSCT is very helpful in evaluating differentiation of the gastric cancer before the operation, which is of great value in planning surgical management and guiding the clinical therapy.