Qiang ZHANG Qi-bao SHI Zhao-xin LIU Ming-min ZHANG. Clin Oncol Cancer Res (2010) 7: DOI /s

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1 DOI /s A Controlled Study on Comparing Differences in CT Perfusion Imaging between s inoculated with VX2 Lung Tumor and Patients with Squamous Cell Carcinoma of the Lung Qiang ZHANG Qi-bao SHI Zhao-xin LIU Ming-min ZHANG Department of Radiology, Inner Mongolia Baotou Tumor Hospital, Baotou , Inner Mongolia Autonomous Region, China. Correspondence to: Qiang ZHANG Tel: zhq @163.com Received November 19, 2010; accepted December 13, cocr@gmail.com Tel (Fax): OBJECTIVE By analysis and evaluation of the perfusion images and perfusion parameters of the rabbits with VX2 lung tumor, the association between the perfusion parameters and tumor angiogenesis of patients with squamous cell carcinoma of the lung has been studied in order to establish a non-invasive and effective way to detect tumor blood supply, which is be able to exhibit hemodynamic data in tumors during cancer treatments. METHODS Fifteen Netherlands rabbits inoculated with VX2 lung tumor (rabbit group) and 25 patients with squamous cell carcinoma of the lung (patient group) received a multi-slice spiral CT perfusion imaging test using the Netherlands PHILIPS Brilliance 16-slice spiral CT and a U.S. MEDRAD binocular highpressure syringe. Image postprocessing was done using the special perfusion software and EBW 4.0 Workstation. Perfusion volume (PV), peak enhanced increment (PEI), transit time peak (TTP), and blood volume (BV) were measured and analyzed. RESULTS In the rabbit group, the values of the PV, PEI, TTP, and BV of the tumor margin were (53.89 ± 13.38) ml/(min ml), (45.71 ± 15.52) Hu, (39.29 ± 10.10) sec, and (31.45 ± 18.19) ml/100 g, respectively; these values of the tumor center were (36.57 ± 14.17) ml/(min ml), (28.64 ± 11.74) Hu, (39.00 ± 9.78) sec, and (19.76 ± 13.95) ml/100 g, respectively; the values of the muscles were (12.45 ± 4.38) ml/(min ml), (10.98 ± 5.03) Hu, (38.86 ± 10.04) sec, and (5.38 ± 2.87) ml/100 g, respectively. The values of the relative perfusion volume (RPV), relative peak enhanced increment (RPEI), and relative blood volume (RBV) of the tumor margin were 4.38 ± 1.45, 3.96 ± 1.45, 9.99 ± 11.7, respectively; these values of the tumor center were 2.14 ± 1.08, 1.83 ± 1.45, 4.17 ± 3.39, respectively. The values of the PV, PEI, BV of the tumor margin vs. the values of the muscles developed t-values, which were , 10.79, and 5.88, respectively (P 0.01), with statistical significance; the values of the PV, PEI, BV of the tumor center vs. the values of the muscles produced t-values, which were 8.67, 7.49, and 4.55, respectively (P 0.01), with statistical significance. The values of the TTP of the tumor margin vs. TTP values of the muscles, and the TTP values of the tumor center vs. TTP values of the muscles developed t-values, which were 1.7 and 0.806, respectively (P 0.05), without statistical significance. In the patient group, the values of the PV, PE, TTP, and BV of the tumor margin were (88.95 ± 30.89) ml/(min ml), (61.87 ± 27.31) Hu, (37.72 ± 12.53) sec, and (18.38 ± 7.2) ml/100 g, respectively; these values of the tumor center were (39.77 ± 18.29) ml/(min ml), (14.57 ± 8.1) Hu, (35.64 ± 12.41) sec, and (11.22 ± 6.02) ml/100 g, respectively; these values of the muscles were (12.45 ± 6.5) ml/(min ml), (6.14 ± 2.66) Hu, (35.68 ± 12.35) sec, and (2.23 ± 1.11) ml/100 g, respectively. The values

2 366 Clin Oncol Cancer Res (2010) 7: of the RPV, RPEI, and RBV of the tumor margin were 8.05 ± 5.04, 8.87 ± 4.32, and ± 8.49, respectively; these values of the tumor center were 2.39 ± 1.68, 2.97 ± 2.1, 3.53 ± 2.82, respectively. The values of the PV, PEI, BV of the tumor margin in the patient group vs. the values of the muscles produced t-values, which were 13.8, 10.85, and 12.22, respectively (P < 0.01), with significant differences; these values of the tumor center vs. the values of the muscles developed t-values, which were 9.158, 6.26, 8.654, respectively (P < 0.01), with significant differences. The TTP value of the tumor margin vs. that of the muscles produced t-value, which was 0.371, and the TTP value of the tumor center vs. that of the muscles developed t-value, which was 1 (P > 0.05), without statistical difference. CONCLUSION CT perfusion imaging technics demonstrates directly dynamic changes of blood flow to tumors, which assists in identifying tumor growth and necrosis, therefore, this research provides an evidence-based guidelines for the treatment of human lung squamous cell carcinoma and has far-reaching clinical significance. KEY WORDS: perfusion imaging, lung neoplasms, controlled study. Copyright 2010 by Tianjin Medical University Cancer Institute & Hospital and Springer Introduction In recent years, incidence trends of lung cancer have gradually increased. Tumor angiogenesis is the focus for laboratory research and clinical research. With the rapid development of computer technology and evolution in CT technic, multi-slice spiral CT perfusion imaging (CTPI), which evaluates vascular function in tumor has become possible, and in addition, it has also been widely used in the evaluation of liver, brain, and kidney and in the test of abnormal blood flow dynamics [1-3]. In this study, the perfusion parameters obtained from VX2 tumor-bearing rabbits and from human lung squamous carcinoma were compared and evaluated, in order to provide evidence-based clinical treatment for lung cancer patients. Materials and Methods Experimental animals Sixteen New Zealand white rabbits, including male and female, with the average weight of 2.68 kg (ranging from 2-3 kg) were purchased from Experimental Animal Center of Inner Mongolia University (animal certificate: XCXK: M ). All the experimental procedures and animal maintenance were confirmed to the strict guidelines of institutional animal ethics committee. Preparation of tumor-bearing rabbit VX2 squamous cell carcinoma lines were provided by Department of Clinical Laboratory, Peking University Institute of Oncology. The tumor cells were added with normal saline to prepare /ml cell suspension. One rabbit was inoculated subcutaneously 1 ml of cell suspension in its thigh to raise transplantation tumor. After the transplanted tumor formed, it was measured based on the following criteria: the mass could be touched from the surface and felt little mobility and tough quality; removed mass was confirmed by pathologic examination and diagnosed as squamous cell carcinoma. Preparation of rabbit models inoculated with VX2 lung cancer cells (rabbit group) After about 2 weeks of the transplantation, the tumor was removed and cut into little pieces and then made into /ml, 10 ml cell suspension. The other 15 rabbits were injected 0.5 ml/rabbit cell suspension into the lung, guided by CT (Netherlands PHILIPS Brilliance 16-slice spiral CT), and at the 7 th, 14 th, and 21 st day after the injection, CT perfusion imaging was conducted respectively. The standards of successful inoculated rabbit model: CT plain scan showed irregular shadow of soft tissue mass, which could become intensity after enhanced. Patient group Case inclusion criteria: patients aged between 30 and 80 years in Inner Mongolia Baotou Tumor Hospital between October 2009 and May 2010; biopsy showed lung squamous cell carcinoma; informed consents were obtained. Before surgery, all the patients who had undergone CT perfusion imaging, and after the surgery, the specimens were tested by immunohistochemistry (VEGF). Exclusion criteria: squamous cell carcinoma was not confirmed by pathological examination or patients with lung squamous cell carcinoma or their family members refused to participate the study. During the period, 25 patients who met these criteria were collected. There were 16 males and 9 females, and the mean age was 45 years, ranging from years. This study was reviewed and approved by the Institutional Review Board of Inner Mongolia Baotou Tumor Hospital. CT scanning group The experimental rabbits fasted 12 h before the scanning. Right before the canning, the rabbits were given a venous indwelling needle through the ear vein. After that, the rabbits were anesthetized with pentobarbital sodium, of which concentration was 0.1 mmol/l and the dose was 1ml/kg. Then the rabbits were fixed on a board with a supine position. A bellyband was used to

3 367 reduce respiratory motion. Model of the static, samelevel dynamic scanning perfusion was used in the experimental rabbits, in which 3-4 ml of the Iohexol (350 mg/ml), a contrast medium was injected at the speed of 0.4 ml/sec, using binocular high-pressure syringe. One second after the contrast medium was injected, the successive scanning was performed for image acquisition. Patient group Model of the static, same-level dynamic scanning perfusion was applied in human body, in which ml of Iohexol (350 mg/ml) was injected at 3-5 ml/sec, using the binocular high-pressure syringe. One second after the injection, the successive scanning was performed for image acquisition. CT scanning parameters Detector array at mm, slice thickness 3.0 mm, pitch 3.0 mm, tube voltage 120 kv, tube current 100 mas, 360 rotation time 0.4 sec, scan interval 6.5 sec (default minimum). The scanning was repeated times within sec to get a complete dynamic curve, showing the contrast agent circulated in lung cancer. CT perfusion Image processing Special perfusion software and EBW 4.0 Workstation were used for image postprocessing. Region of interest (ROI) The ROI included aorta, tumor margin, tumor center, and the ipsilateral muscle. ROI selection method: at the aorta, tumor margin, tumor center, the ipsilateral muscle of the same cases at the same point PV (perfusion volume), PEI (peak enhanced increment), TTP (transit time to peak), BV (blood volume) were measured. RPV (relative perfusion volume), RPEI (relative peak enhanced increment), RBV (relative blood volume) were calculated using the formula. Main perfusion parameters and the calculation Deconvolution model was used to calculate the values of the main perfusion parameters, PV, PEI, TTP, and BV. Formulas used were: RPV = foci PV/normal muscle PV, RPEI = foci PEI/normal muscle PEI, RBV = foci BV/ normal muscle BV. Generation of perfusion color graph CT perfusion software was applied to get image reformation and to process the false color image. After that, the diagrams of PV, PEI, TTP, BV were employed to evaluate comprehensively the perfusion status in the lesions. Immunohistochemistry Using streptavidin biotin-peroxidase method (SP) to identify CD34. The cytoplasm stain of vascular endothelial cells (VEGF) presented in brown, or brown-yellow color, which was considered that CD34 was positive. VEGF expression was divided into (-) (+++) with a total of 4 levels. Sections were viewed under light microscope at 200 times, and the number of the microvessels, which presented in brown color was counted in 5 different fields. The number of the positive cells < 5% was regarded as negative (-), 5%-25% considered as weak positive (+), 26%-50% regarded as positive (++), > 50% considered as strong positive (+++). Statistical analysis SPSS 13.0 statistical package was used for the statistical analysis. Paired parameters of tumor margin muscle, tumor center, and muscle were analyzed with t-test. P < 0.05 was considered different and P < 0.01 was considered a statistically significant difference. Results CT perfusion parameters of interest regions in the rabbit group Values of the PV, PEI, TTP, and BV in the margin area are presented in Table 1. Values of the RPV, RPEI, and RBV in the margin area are presented in Table 2. The values of PV, PEI, and BV from the tumor margin area vs. the same values from the muscles generated t-values, which were , 10.79, 5.88, respectively, with the P < 0.01, indicating that the differences in the t-values were significant. The values of PV, PEI, and BV of the tumor center vs. the same values of the muscle developed t-values, which were 8.67, 7.49, 4.55, respectively, with the P < 0.01, indicating that the differences in the t-values were significant. TTP of the tumor margin vs. muscle and TTP of the tumor center vs. that of the muscle respectively generated t-values, which were 1.7, 0.806, respectively (P > 0.05). CT perfusion parameters of the interest regions in the patient group The values of RPV, RPEI, and RBV of the tumor margin are presented in Table 4. The values of PV, PEI, and BV of the tumor margin in the patient group vs the values of the muscles developed t-values, which were 13.8, 10.85, (P < 0.01), with statistical differences; these values of the tumor center vs the values of the muscles produced t-values, which were 9.158, 6.26, (P < 0.01), with statistical differences. TTP values of the tumor margin vs. the TTP values of the muscles developed t-values, which was 0.371; TTP values of the tumor center vs the values of the muscles produced t-values, which was 1 (P > 0.05), without statistical difference.

4 368 Clin Oncol Cancer Res (2010) 7: Table 1. Perfusion imaging parameters of the rabbits with VX2 lung tumor. PV [ml/(min ml)] PEI (Hu) TTP (sec) BV (ml/100 g) Tumor margin ± ± ± ± Center ± ± ± ± Muscle ± ± ± ± 2.87 PV = the perfusion values, PEI = peak enhancement increments, TTP = transit time to peak, BV = blood volume Table 2. Relative values of perfusion imaging parameters of the rabbits with VX2 lung tumor. RPV RPEI RBV Lesion edge 4.38 ± ± ± 11.7 Lesion center 2.14 ± ± ± 3.39 Note: RPV = the relative perfusion values, RPEI = relative peak enhancement increments, RBV = relative blood volume Table 4. Relative value of perfusion imaging parameters of different regions of tumor in the patients with squamous cell carcinoma of the lung. RPV RPEI RBV Tumor margin 8.05 ± ± ± 8.49 Tumor center 2.39 ± ± ± 2.82 Note: RPV = the relative perfusion values, RPEI = relative peak enhancement increments, RBV = relative blood volume Table 3. Perfusion imaging parameters of the patients with squamous cell carcinoma of the lung. PV [ml/(min ml)] PEI (Hu) TTP (sec) BV (ml/100 g) Tumor margin ± ± ± ± 7.2 Tumor center ± ± ± ± 6.02 Muscle ± ± ± ± 1.11 PV = the perfusion values, PEI = peak enhancement increments, TTP = transit time to peak, BV = blood volume CT perfusion As the hemodynamic parameters were different in the tumor growing stages, and human lung squamous cell carcinoma also had different pathological grades as tumor grew. For the tumor size of the rabbits larger than 2 cm (Fig.1.1A-1D), its RPV and RPEI from the tumor margin increased gradually, and RBV increased significantly. Its RPV, RPEI, and RBV from the tumor center all decreased. The same values of the moderately differentiated human lung squamous cell carcinoma in the patient group were similar to those values in the rabbit group. Regarding the tumor size of the rabbit group less than 2 cm and no sub-foci appearing in the surrounding tissue of the tumor, its RPV and RPEI of both tumor margin and tumor center were lower, but the RBV of both regions were higher. The same values of the welldifferentiated squamous cell carcinoma of the lung in the patient group were similar to those values in the rabbit group. For the tumor size of the rabbit less than 2 cm and sub-foci appearing in the surrounding tissue of the tumor (Fig.1.2A-2D), its values of RPV, RPEI, and RBV of both tumor center and tumor margin increased significantly. The same values of the poorly differentiated squamous cell carcinoma of the lung in the patient group were similar to those values in the rabbit group. Immunohistochemistry In the rabbit group, lesions smaller than 2 cm were in 7, the lesions larger than 2 cm in 8, and the lesions larger than 2 cm with sub-lesions appearing in the surrounding tissues of the tumor were in 5. VEGF-positive (++) presented in larger size of the tumor (Fig.1.1E). In the patient group, poorly differentiated squamous cell carcinomas were in 12 cases, moderately differentiated squamous cell carcinoma in 8 cases, and well-differentiated squamous cell carcinomas in 5 cases. VEGF-positive (+++) presented in the tumor margin and tumor center of the poorly differentiated lung squamous cell carcinoma (Fig.1.2E). VEGF positive (+++) presented in the tumor margin of the moderately differentiated squamous cell carcinoma. VEGF (+) presented in both rabbits with VX2 lung tumor without appearing sub-foci and well-differentiated squamous cell carcinoma of lung in the patients. VEGF expression was higher in the tumor located in the lung tissue and in the tumor adjacent to bronchi than that of tumor located in the bronchial lu-

5 369 Fig.1. 1A-1D, in the rabbit group, soft tissue mass in the left lung lower lobe shown on the enhanced CT scan was irregular (1A). Perfusion scanning images showed that the parameters of tumor region, PV (1B), PEI (1C), and BV (1D) were significantly higher than those of normal muscle tissue; 2A-2D, in the patient group, poorly differentiated squamous cell carcinoma of the lung, soft tissue mass in the right lung lower lobe shown on the enhanced CT scan was irregular (2A), and swelling hilar lymph nodes also presented on the scan Perfusion scanning images showed that parameters of the tumor area, PV (2B), PEI (2C), and BV (2D) were higher than those of normal muscle tissue, and the sign of circular blood vessels surrounding the tumor could be seen, and enlarged lymph nodes also showed significantly stained; 1E shows the rabbits with VX2 lung tumor, immunohistochemistry showed that the tumor can be seen around the proliferated endothelial cells, which had obvious stain. CD34 immunohistochemistry showed that the tumor blood vessels were stained brown (SP 200); 2E shows the poorly differentiated human lung squamous cell carcinoma immunohistochemistry revealed the proliferated capillaries around the tumor with obvious, stain. CD34 immunohistochemistry showed that the tumor blood vessels were stained brown (SP 200); 3A-5B, the scattered diagram of the perfusion parameters of the rabbit with VX2 lung tumor and the human lung squamous cell carcinoma. The edge RPV scattered diagram (3A) showed normal distribution, and the deviation points indicated poorly differentiated human lung squamous cell carcinoma. The central RPV scattered diagram (3B) demonstrated normal distribution, and deviation points represented well-differentiated human lung squamous cell carcinoma. The edge RPEI scattered diagram (4A) showed a normal distribution and deviation points meant well-differentiated human lung squamous cell carcinoma. The central RPEI scattered diagram (4B) showed a normal distribution. The edge RBV scattered diagram (5A) showed a normal distribution, and the deviation points indicated that the rabbits with VX2 lung tumors had sub-foci. The central RBV scattered diagram (5B) demonstrated normal distribution, and the deviation points meant that the rabbits with VX2 lung tumor developed sub-foci.

6 370 Clin Oncol Cancer Res (2010) 7: men. The lower the differentiation level in histology was, the higher the VEGF expression and MVD were. Discussion With the development of clinical oncology, the introduction of evidence-based medicine, and wide application of new technologies, the clinical diagnosis and treatment of cancer have been required to meet higher standards, therefore, there is an urgent need for more basic research to prove the feasibility of new developed modalities of diagnoses and the treatments. Comparative studies of CT perfusion imaging between the rabbits with VX2 lung tumor and the patients with squamous cell carcinoma of the lung have not been reported in literature to date. Tumor angiogenesis plays an important role in the development, invasion and metastasis of solid tumors, and significantly affects the biological behavior of the tumor and prognosis of the patients [4-6]. The preferred cancer treatment is the targeted therapy (not or less damage to normal tissues), which requires imaging technology to accurately detect and quantificat the angiogenesis. De Keyzer et al. [7] reported that the effectiveness of cancer treatment could be measured by increased necrotic tissue within the tumor and reduced blood perfusion to the tumor. A functional CT can measure perfusion volume and blood volume in the tumor [8] ; CT perfusion imaging can be used to measure physiological parameters of the blood supply to tumor and to other tissues, and these physiological parameters are closely related to the angiogenesis seen under a microscope [9,10]. These parameters can be used to quantitatively analyze the blood supply to the tissues, and the regular evolution of these hemodynamic parameters can be an objective assessment of tumor microcirculation, angiogenesis and the patients early reactions to treatment [11-13]. It is a potential way to identify if the chemotherapy is effective or not in early stage and to help change the treatment schedule so as to get better outcomes [14]. With higher perfusion volume and blood volume in the lung tumor, high grade of malignancy, and extensive angiogenesis in the tumor, the short-term effects of the treatment could be better [15]. Side effects caused by cancer treatment may cause patients suffering severe physical and psychological problems, leading to uncertainties of clinical treatment, therefore, for malignant tumors, relative perfusion parameters (RPV, RPEI, and RBV) of the CT perfusion imaging should be carefully considered. For cancer patients who have developed tolerance to cancer treatments, these parameters can reflect tumor progress and changed microcirculation and angiogenesis in the tumor. Based on the findings reflected by the parameters, individualized treatment plan could be achieved. The research of lung cancer on its occurrence and progress requires people to be the subjects, but for ethical reasons, such experiments are not allowed. Researchers have to establish animal models, being inoculated with human cancer cell lines, which grow the same type of cancer as inoculated cancer cell line, for this kind of research in order to find out the regulation existing in the animal models, which can be extended to humans. A study of cancer treatment led by Samir [16] based on animal model revealed that the law in the development and metastases of the inoculated tumor in animal model is similar to that in human cancer. In this research of CT perfusion imaging on rabbits inoculated with VX2 lung tumor, the same morphology shown by the patients with lung squamous cell carcinoma and by the rabbits with VX2 lung tumor was found and the perfusion parameters of both rabbits with VX2 lung tumor and human lung squamous cell carcinoma were similar. CT perfusion parameters measured from different sizes of tumors in the rabbit group and in the patient group were quantitatively analyzed using paired t-test, and it was found that there were correlations among tumor growth characteristics, pathological types and CT perfusion imaging parameters: (1) When tumor size was less than 2.0 cm, with low grade of malignancy, its RPV and RPEI were all low, but the RBV was higher; with the tumor gradually increased in size, its RPV, RPEI, and RBV were all increased significantly. (2) When the tumor size was larger than 2.0 cm, the RPV and RPEI of the tumor margin were gradually increased, and its RBV was significantly increased, however, the RPV, RPEI, and RBV of the tumor center were decreased. (3) The higher the malignant tumor grade was, the more significant the RPV, RPEI, and RBV of the tumor center and tumor margin were. (4) Moderately differentiated squamous cell carcinoma with the tumor size larger than 2.0 cm, appeared colliquation in tumor center, forming a hollow center, and its RPV and RPEI of the tumor margin were obviously increased, and its RBV was significantly increased. (5) For the tumor occurring in the surrounding tissues of bronchi, its, RPV, RPEI, and RBV of the tumor margin and tumor center were significantly higher than those of the tumor occurring in the bronchial lumen. This research demonstrated that when tumors progressed in the rabbit group and in the patient group, angiogenesis in tumors was increased, and the PV, PEI, and BV of the tumors were accordingly increased, with the increased RPV, RPEI, and PBV. Scattered diagram of the RPV, RPEI, and PBV showed a normal distribution, with a few points off (Fig.1.3A-5B). In the edge RPH scattered diagram of the human lung squamous cell carcinoma, the deviation points showed the poorly differentiated squamous cell carcinoma. In the central RPH scattered diagram, deviation points downward demonstrated well-differentiated squamous cell carcinoma, and the upward deviation points represented moderately differentiated squamous cell carcinoma. In the edge RPEI scattered diagram, the upward deviation points showed poorly differentiated squamous cell carcinoma, and the

7 371 deviation points downward represented well-differentiated squamous cell carcinoma. In the central RPEI scattered diagram, deviation points indicated poorly differentiated squamous cell carcinoma. In the edge RBV scattered diagram, deviation points upward represented poorly differentiated squamous cell carcinoma, and deviation points downward demonstrated well-differentiated squamous cell carcinoma. In the central RPEI scatter diagram of the rabbit group, the deviation points upward meant the tumor size larger than 2 cm, with subfoci around, and the deviation points downward showed that the tumor size was greater than 2 cm and necrosis in the tumor appeared. In the edge RBV scattered diagram, the deviation points upward meant the tumor size larger than 2 cm, with sub-foci around and the deviation points downward represented the tumor size greater than 2 cm, with necrosis in the center. In the central RBV scattered diagram, deviation points indicated the tumor size larger than 2 cm, with multiple sub-foci, which could be associated with the levels of differentiation of malignant tumors, or could be associated with different growth stages of tumors, because the differences in number of microvessels in tumors and in functions that the tumor microvessels behaved correlated to the levels of differentiation and stages of malignant tumors [17,18]. When the malignant levels of tumors were higher, blood perfusion was increased, and the mediastinal and metastatic lymph nodes in the hilar showed enhanced image, with increaased blood perfusion [15]. CT perfusion imaging technics demonstrates directly dynamic changes of blood flow to tumors, which assists in identifying tumor growth and necrosis. Comparative analyses of the perfusion parameters between the rabbits inoculated with VX2 lung tumor and the patients with squamous cell carcinoma of the lung revealed that the laws of tumor growth, microcirculation, and hemodynamics of the rabbits with VX2 lung tumor are similar to those of the patients with lung squamous cell carcinoma. This research of the rabbits with VX2 lung tumor provides an evidence-based guideline for the treatment of human lung squamous cell carcinoma and has farreaching clinical significance. By analysis and evaluation of the perfusion images and perfusion parameters of the rabbits with VX2 lung tumor, the association in the perfusion parameters and the tumor angiogenesis between the experienmental rabbits and the patients with lung sqemous cell carcinoma has been studied in order to establish a non-invasive and effective way to detect tumor blood supply, which is able to exhibit hemodynamic data in tumors during cancer treatments. 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