As a non-invasive functional radiographic imaging method, perfusion computed tomography (PCT) permits the evalu-ation of non-small-cell lung cancer (NSCLC) angiogenesis and response to therapy by demonstrating alterations in NSCLC vascularity. PCT performed shortly after initiating therapy may provide a better evaluation of physiological changes rather than conventional size as-sessment obtained by response evaluation criteria in solid tumors. Based on the angiogenesis principle of NSCLC, the main evaluation indexes of PCT are blood flow, blood volume, mean transit time, permeability surface, and peak enhancement index. The relationship between PCT and the indexes of vascular normalization may have implications for exploring the predictive model of efficacy and prognostic factors of NSCLC. The cavity of microvessel in NSCLC and expression of VEGF factors are closely related to PCT imag-ing. According to PCT assessment, pathological classification and histological type of NSCLC play significant roles. However, techni-cal limitations, reproducibility of blood flow parameters, radiation dose, and volume of contrast medium delivered to the patient are some issues in this type of investigation. With the development of PCT technology and anti-angiogenesis drugs for NSCLC, more mo-lecular imaging markers and standardized targeted therapies will be available. Such advancements will provide a wider space for the as-sessment of NSCLC treated with anti-angiogenic therapy using PCT.

Objective To assess the CT perfusion characteristics of breast diseases. Methods Twenty-two patients with fibroadenoma accompanied with cyst (n=1), other benign diseases (n=5), and carcinomas (n=16) underwent breast CT scan. CT perfusion was performed for breast with cine mode (0.5 s per rotation ) on a multislice CT scanner ,120 kV, 60 mA, 4?5 mm collimation. Contrast injection was done by using 50 ml nonionic contrast agent ( 300 mg I/ml ), at a flow rate of 4 ml/s with a power injector, 5 seconds delay, and data acquisition lasted for 50 seconds. These data were processed on a GE AW 4.1 workstation using perfusion 3 software package, and the mean BF, BV, MTT and PS were measured and statistically analyzed. Results The mean BF, BV, MTT and PS in carcinoma were (33.55? 28.40) ml?min -1 ? 100 g -1 , (5.60?3.08) ml/100 g, (15.37?6.41) s, (18.71?10.42) ml?min -1 ?100 g -1 . The mean BF, BV, MTT and PS in contralateral normal breast of carcinoma were (10.36?9.44) ml?min -1 ? 100 g -1 , (0.70?0.22) ml/100 g, (13.55?7.27) s, (1.54?1.74) ml?min -1 ?100 g -1 . The mean BF, BV, and PS between carcinoma and normal breast were statistically significant (P0.05). The mean BF, BV, MTT and PS in fibroadenoma were (62.57?19.62) ml?min -1 ?100 g -1 , (7.37?1.30) ml/100 g, (11.24?3.34) s, (27.63?3.87) ml?min -1 ?100 g -1 . The mean PS between carcinoma and fibroadenoma was statistically significant (P0.05). The mean BF, BV, MTT and PS in benign lesion were (7.65?10.24) ml?min -1 ?100 g -1 , (1.23?0.97) ml/100 g, (14.94?10.68) s, (1.81?1.72) ml?min -1 ?100 g -1 . The mean BF, BV, and PS between carcinoma and benign lesion were statistically significant (P0.05). Conclusion MSCT perfusion may reflect the features of breast diseases, and provide valuable hemodynamic message. These parameters have a value in diagnosis of breast diseases and are helpful for differential diagnosis.

Objective To investigate the role of CT in the diagnois of superior vena cava syndrome secondary to pulmonary carcinoma. Method Fifty patients with pulmonary carcinoma resulting in SVCS were confirmed by pathological examinations. Relationship between anatomical distribution and gross type of pulmonary carcinoma and modes of pulmonary carcinoma resulting in SVCS were analyzed retrospectively and statistically. Correlation among obstructive degree of SVC, opening of collateral pathway and swelling of chest wall was analyzed retrospectively and statistically. Results For modes of pulmonary carcinoma resulting in SVCS, direct invasion of pulmonary carcinoma was 7 patients, metastasis of lymph node was 16 patients and both of the two was 27 patients.Modes of pulmonary carcinoma resulting in SVCS were different for different gross types of pulmonary carcinoma in different pulmonary lobes ( x2 = 30.012,P ＜ 0.05). On CT appearances of secondary lesions, cases of simple constitution and opening of collateral pathway, simple swelling of chest wall, both of the two and neither of the two were 14 patients, 12 cases, 15 patients and 9 patients in order on CT. With SVC obstruction at different extent,constitution and opening of collateral pathway and swelling of chest wall were different ( x2= 12.881, P ＜ 0.05).Conclusions SVCS resulted from pulmonary carcinoma can be diagnosed by contrast enhanced CT.

Objective To analyze the correlation between renal blood flow (BF)of CT perfusion and effective renal plasma flow (ERPF)of radionuclide labeled microspheres.Methods CT perfusion was applied to 26 cases of renal cell carcinoma (RCC)in order to obtain the average unit BF of the target layer of the uninjured lateral kidney.For the renal image of the uninjured lateral kidney in the nephrographic phase (NP),we used the value of maximal renal cross-sectional area times the value of renal maximal height as the standardized volume.The product of this standardized volume and average unit BF could be used as an approximation of total re-nal blood flow,which was a standardized renal BF value.Meanwhile,we took radionuclide labeled microspheres into practice to ob-tain an ERPF value of the corresponding uninjured lateral kidney.The correlation between standard renal BF and ERPF was obtained by using Pearson chi-square test.Results The standard renal BF values of the uninjured lateral kidney for the group of 26 cases of RCC ranged from 620.59 to 820.76 mL·min-1 ·g-1 ·cm3 (mean=718.87 ±58.40 mL·min-1 ·g-1 ·cm3 ),and the values of ERPF tested by radionuclide labeled microspheres ranged from 244 to 41 1 mL/min (mean= 320.54 ± 55.71 mL/min).The two groups were positively correlated (r=0.754,P <0.01).Conclusion CT perfusion imaging of the kidney,to some extent,has the potential to replace renal functional examination of radionuclide labeled microspheres.

Objective:To examine the features of multislice spiral computed tomography (MSCT) in micropapillary-predominant lung adenocarcinomas to improve the understanding of this type of lung cancer. Methods:The MSCT features of 18 cases with micro-papillary-predominant lung adenocarcinoma (micropapillary component>50%) confirmed by histopathology were analyzed retrospec-tively. Results:Among the 18 cases of lung cancer, 1 was diffuse, 3 were central, and 14 were peripheral lung cancer (PLC). The size of the adenocarcinomas in the 14 PLC cases ranged from 1.3 cm to 8.5 cm, with an average of 3.56 cm, including the size of 8 cases greater than or equal to 3 cm. Among the 18 cases, 13 were lobulated, 9 showed spicule signs, 7 showed pleural indentation signs, 5 had pleural adhesions, 1 had bronchial truncation (i.e., cut-off sign), and 4 were surrounded by obstructive inflammation. In addition, calcifi-cation was observed in one case, uneven density in two large lesions, air bronchus sign in four, and solid and ground-glass mixed densi-ty in two. Among the total number of cases, a variety of the measurable enhanced CT values (ΔCT) of lesions were found in 16, ranging from 13 HU to 80 HU, with an average of 47.5 HU, of which 15 were cases ofΔCT≥15 HU and 15 were cases ofΔCT≥20 HU. Pleu-ral thickening was observed in two cases with pleural effusion, and pleural metastasis in one case was confirmed by histopathology. One case with pleural effusion suffering pleural metastasis was confirmed. Ground-glass density nodules in both lungs were observed in one case, with a few bilateral pleural and pericardial effusions. Eight cases had mediastinal or hilar enlarged lymph nodes with uneven density enhancement, and lymph node metastasis was pathologically confirmed in six cases. Lymph node metastasis was found in four cases, but no apparent enlargement of lymph nodes in MSCT was observed. Conclusion:Micropapillary-predominant lung adenocarci-nomas were common in non-smoking elderly female patients, whose lung cancer cases were mostly PLC. The typical features of PLC include lobulation, spicule, and pleural indentation signs. Solid density ranked first in the PLC cases, with evident enhancement and high rate of lymph node metastasis.

Objective To explore the correlation between epidermal growth factor receptor (EGFR) gene mutations and computed tomography (CT) characteristics in lung adenocarcinoma.Methods Chest CT scan results of 200 postoperative lung adenocarcinoma patients were retrospectively studied,the EGFR gene mutations detection results were statistically analyzed,and the correlation between EGFR gene mutations status and CT characteristics was investigated.Results Single factor analysis results showed that non smoking,female patients,air bronchogram sign and small tumor diameter were significantly associated with EGFR gene mutations (P＜0.05),and the incidence of GGO in the EGFR gene mutation group was higher than that in the wild group,but no statistical significance was found (P＞0.05),while other clinical and CT signs,such as age,lobulation,spicule,calcification,cavity and pleural indentation were not associated with EGFR gene mutations (P＞0.05).Logistics regression analysis results showed that non smoking and air bronchogram sign were significantly associated with EGFR gene mutations (P＜0.05),but gender and tumor size were not associated with EGFR gene mutations(P＞0.05).Conclusions Non smoking and air bronchogram sign may be used as predictive factors for EGFR gene mutations in lung adenocarcinoma.

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Objective:To study the predictive value of combining alpha-feto protein (AFP) with contrast-enhanced MRI imaging features in predicting incidence of microvascular invasion (MVI) in patients with hepatocellular carcinoma.Methods:The data of 206 patients with hepatocellular carcinoma treated at Tianjin Medical University Cancer Institute and Hospital from January 2017 to April 2019 were retrospectively analyzed. There were 179 males and 27 females, with an average age of 58.7 years. The roles of preoperative MRI imaging features and clinical data on predicting the incidence of MVI in patients with hepatocellular carcinoma were evaluated by univariate and multivariate logistic regression analyses. Multivariable regression analysis was then used to plot a nomogram.Results:There were 86 patients (41.7%) with MVI positivity and 120 patients (58.3%) with MVI negativity. Multivariate logistic regression analysis showed that AFP >400 μg/L ( OR=3.318, 95% CI: 1.243-8.855, P=0.017), two-trait predictor of venous invasion (TTPVI) ( OR=13.111, 95% CI: 6.797-28.119, P<0.001), diffusion weighted imaging/T 2 weighted imaging (DWI/T 2WI) mismatch ( OR=17.233, 95% CI: 4.731-44.490, P<0.001), and rim enhancement( OR=5.665, 95% CI: 2.579-18.152, P=0.013) predicted increased risks of MVI in patients with hepatocellular carcinoma. The constructed nomogram directly predicted the risk of MVI in these patients. Conclusions:AFP>400 μg/L, TTPVI, DWI/T 2WI mismatch and rim enhancement were independent risk factors in predicting MVI in patients with hepatocellular carcinoma. This predictive model of MVI which was based on multivariate logistic regression analysis was helpful to clinicians in making individualized treatment plans for patients with hepatocellular carcinoma.

Objective To investigate the influence of“double low”technology(low concentration iodinated contrast agent and low-dose scan) combined with body mass index(BMI) on radiation dose and image quality of contrast-enhanced upper abdominal CT examination. Methods One hundred and twenty patients who received upper abdominal enhanced CT examination were randomly divided into 4 groups:group A1, the iodinated contrast agent iodixanol(270 mg/ml), BMI<18.5 kg/m2 and 80 kVp;group A2, the iodinated contrast agent iodixanol(270 mg/ml), 18.5 kg/m2≤BMI≤24.9 kg/m2 and 100 kVp; group B1, the iodinated contrast agent ioversol(320 mg/ml),<18.5 kg/m2 and 120 kVp; group B2, the iodinated contrast agent ioversol(320 mg/ml), 18.5 kg/m2≤BMI≤24.9 kg/m2 and 120 kVp. Image quality was subjectively scored, the objective parameters(noise, CT values of abdominal aorta and liver parenchyma, contrast noise ratio of abdominal aorta and liver parenchyma) were evaluated and radiation dose was recorded. The differences of the indexes between A1 and B1 groups, A2 and B2 groups were compared with Mann-Whitney U test and pared-samples t test. Results All CT images were good. No images with 4 scores were obtained. No significant difference was found between group A1 and B1, between group A2 and B2(P>0.05). There was no significant difference in contrast noise ratio of liver parenchyma(P>0.05), while significant differences existed in CT values of abdominal aorta and liver parenchyma, contrast noise ratio of abdominal aorta between group A1 and B1(P<0.05). Significant differences existed in the parameters above mentioned between group A2 and B2, respectively(P<0.05). Radiation dose was lower in group A1 than in group B1 and in group A2 than in group B2(P<0.05), respectively. Radiation dose was decreased by 40.1%(0.89/2.22) in group A1 than group B1 while radiation dose decreased by 56.9%(3.02/5.31) in group A2 than group B2. Conclusion According to BMI, the low concentration iodinated contrast agent and low-dose scan CT scanning technology could effectively reduce radiation dose and generate ideal images during the contrast-enhanced upper abdominal CT examination.

Objective To summarize the features of multislice spiral computed tomography (MSCT) examination of gastrointestinal stromal tumors (GISTs),and investigate the relationship between predictors and risk of MSCT examination for GISTs.Methods The clinical data of 110 patients with GISTs who were admitted to the Tianjin Medical University Cancer Institute and Hospital from July 2011 to February 2014 were retrospectively analyzed.All the patients received 64-slices spiral CT (64S-SCT) or 16-slices spiral CT (16S-SCT) scan,and the data were transported to the PACS work station for multiplanar reconstruction.All the tumor samples were collected during operation and diagnosed by morphological manifestation and immunohistochemistry of tumors.Very low,low,and medium risk of GISTs were regarded as lower risk grade,and high risk of GISTs as high risk grade.The univariate analysis and multivariate analysis about features of imaging and risk were done by chi-square test and multivariate logistic regression model.Results Tumors located at the stomach in 81 cases,small intestines in 26 cases and colorectum in 3 cases.Diameter of tumors was 0.8-25.0 cm.Smaller tumors were in round or oval shape with well demarcated boundary,and larger tumors were irregular with unclear boundary.Endo-luminal growth of lessions was detected in 25 cases,duplex growth in 35 cases and extra-luminal growth in 50 cases.Enhanced CT scan showed that most of tumors in 105 patients demostrated moderate and high enhancement,heterogeneous enhancement in 74 cases,low density sacvariable necrosis area without enhancement in 60 cases and superficial,cracked-like and deep ulcer without calcification,metastasis and ascites in 23 cases.According to the features of GISTs by MSCT examination,location of tumor,diameter,shape,boundary,growth,enhancement,cystic necrosis,ulcer and metastasis were risk factors affecting risk classification of tumors by univariate analysis (x2=7.442,49.966,31.513,46.038,13.836,16.626,23.489,8.280,6.811,P ＜0.05).Diameter of tumor more than 10 cm and ulcer were independent risk factors affecting risk classification of tumors by multivariate analysis (OR =9.927,0.070 ; 95％ confidence intewal:1.888-52.180,0.012-0.398,P ＜ 0.05).Conclusion There is a characterization in the location,diameter,shape,boundary of tumor,growth,enhancement,cystic necrosis,ulcer and metastasis,and diameter of tumor more than 10cm and ulcer are independent risk factors affecting the risk classification of GISTs.