The Study On 64-detector Spiral CT Perfusion And Its Correlation With Angiogenesis Of Solitary Pulmonary Mass

Background and Purpose:VEGF(vascular endothelial growth factor), MVD(microvascular density, MVD) are the gold standard in assessing tumor angiogenesis, but the kind of determining methods by immunohistochemical method mark can't dynamic observation of vivo angiogenesis and functional. The research is to assess the clinic value of 64-detector spiral CT perfusion imaging (CTPI) in diagnosising and differentiating solitary pulmonary mass. To assess the feasibility of 64-detector spiral CT perfusion imaging in evaluating the tumor angiogenesis, by studying the correlation between the parameters, time-density curve (TDC) of CTPI and MVD and vascular endothelial growth factor (VEGF) in solitary pulmonary mass.Materials and methods:(1) 83 cases of solitary mass (size≤5.0cm) in lung from December 2008 to November 2009 who wer detected by radiographing or plain CT scanning, were chosen to perform perfusion scanning. Among them,2 cases near facies diaphragmatical,3cases are too small, patients are uncooperative. So summarizes 78 cases with successful perfusion, among them,1 case was abnormal thickening vessel, lease was interlobar effusion, so 76 cases with successful perfusion confirmed by pathology (50 cases confirmed by surgery).(2) All patients first underwent unenhanced CT scanning through the whole lung with GE Light-Speed VCT 64-detector spiral CT scanner. Chose the largest section as the center section.Then eight adjacent sections locating the center of the lesion were chosen to be the target sections. For all scanning, following parameters:120 KV,180～220 mA, slice thickness 5mm×8i, scanning extent 4cm, cine full, delay time 5s, axlial scanning, total time 50s, exposure time 25s, we got 200 images. Then every 20s 1 scanning in the following 200s, scanning condition invariably, we got 80 images. Standard algorithm reconstructed images. Ioversol (320mg I/ml),50 ml, infusion rate of 4ml/sec, infected by forearm superficial vein.(3) Data analysis was performed with body tumor protocol of CT Perfusion 3 (the Imaging workstation of Advantage Window 4.3, GE Medical Systems). The computer could automatically create maps of blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface (PS). The perfusion parameter values were recorded and the means were calculated respectively.(4) Titting TDC was analyzed with emphasis on it's shape and net enhanced vaue, peak height (PH).(5) 50 cases of surgical tissue samples were determined by hematoxylin and eosin (HE) staining. The expressions of CD34 and VEGF in 50 cases were detected by immunohistochemistry staining, then the MVD counting was performed and the expression of VEGF was recorded. Statistical analysis was performed with spss 16.0 software (one-way ANONA, SNK method and related analysis.Results:(1) Benign mass 8 (tuberculoma 8); inflammatory mass 9 (inflammatory pseudotumor 4, inflammatory segmental consolidation 2, lung abscess 2, lung cyst concurrent infection 1); malignant mass 59(squamous carcinoma 23, adencarcinoma 27, adenosquamous carcinoma 1, mucoepidermoid carcinoma 2, bronchioalveolar carcinoma 2, carcinoid 2, small cell lung cancer 2). Of 50 surgical cases tuberculoma, inflammatory and malignant mass were 5,3and 42.(2) There were some differences in the plain CT signs of pulmonary masses among the three groups. The signs of smooth contour, non- or shallow-lobulation and long speculation were more common in the benign; and edge unsharpness or wedge-shaped appearance were seen more often in the inflammatory; while the signs of irregularity, lobulation, short speculation and pleural indentation were more obvious in the malignant.(3) BF,BV and PS from inflammatory and malignant were higher than those of the tuberculoma(P<0.01). No statistically significant differences in BF and BV from both the inflammatory and the malignant(P>0.05); MTT from the malignant was higher than that of the tuberculoma, but there was no statistically difference in MTT between the tuberculoma and the inflammatory or between the inflammatory and the malignant(P>0.05).(4) The enchancement degree between the tuberculoma, inflammatory and malignant mass were significant different. There were statistically differences between the tuberculoma and malignant mass in enchancement peak value and CT value (200s) (P<0.05), there was statistically differences between the inflammatory and malignant mass in CT value (200s). The malignant mass were enchanced equally,unequally, as well as surrounding enchancement, while most of the non-malignant mass were no enchancement or thin-wall surrounding enchancement.(5) There were statisticant differences in the distribution of the fitting TDC types among the three groups of 50 cases. The fitting TDCs from the tuberculoma either leveled off with a rather low summit. Most of the inflammatory presented fast-up-down fitting TDCs with a rather high summit. However, the fitting TDCs from the malignant rose dramatically at the beginning but then dropped slightly or showed no dropping.(6) In the three groups of 50 cases, MVD and VEGF expression from the three groups were statistically significant differences, inflammatory and malignant were higher than the tuberculoma(all P<0.05), the shape of the malignant angiogenesis often irregular.(7) In addition to MTT, the other perfusion parameters,enchanced indicators and MVD,VEGF expression were positively correlated(P<0.05).Conclusions:1. Plain sign and enchancement degree between benign and malignant mass are different.2. BV,BF and PS can contribute to the discrimination of the tuberculoma,inflammatory and malignant.3. Combined analysis of the types and summits of fitting TDCs can help to differentiate the tuberculoma from the malignant and the inflammatory, but the contribution to differentiating between the malignant and the inflammatory is limited.4. In addition to MTT, the other perfusion parameters and MVD,VEGF expression were positively correlated (P<0.05).5. MDCT perfusion imaging can reflect the solitary pulmonary mass angiogenesis, and can provide the quantitative perfusion information, thus it provides a new method to assess the angiogenesis state of lung cancer in vivo.