[Imaging and Clinical Characteristics of Primary Pulmonary Mucoepidermoid Carcinoma].

Objective To improve the understanding and diagnostic accuracy of pulmonary mucoepidermoid carcinoma(PMEC) by analyzing the imaging and clinical characteristics.Methods The clinical and CT data of 27 cases of PMEC confirmed by histopathology in the First Medical Center of Chinese PLA General Hospital from January 2016 to December 2020 were retrospectively analyzed,including the location,size,margin,density,enhancement characteristics,accompanying signs,and pathological grade.Results The 27 cases included 6(6/27,22.2%) of large airway type,14(14/27,51.9%) of hilar type,and 7(7/27,26.9%) of peripheral type.The CT manifestations of 20 cases of large airway and hilar PMEC were soft-tissue nodules or mass with clear boundary in the lumen of the trachea and main bronchi,including 6 cases of mild enhancement,4 cases of moderate enhancement,5 cases of marked enhancement,and 5 cases of uneven enhancement.Three of the 20 cases showed calcification.The 7 cases of peripheral PMEC showed soft-tissue nodules or masses in the lungs,including 3 cases of mild enhancement,1 case of moderate enhancement,and 3 cases of marked enhancement. Obstructive pneumonia or atelectasis and bronchiectasis with mucus plug formation occurred in 16(16/27,59.3%) cases,lymph node metastasis in 9(9/27,33.3%) cases,and multiple organ metastasis in 8(8/27,29.6%) cases.Age(t=-3.132,P=0.005),enlarged lymph node (χ2=9.281,P=0.003),and distant metastasis(χ2=7.816,P=0.008) were statistically significant in the low-grade group and high-grade group. Conclusion PMEC have some unique imaging features,and recognizing these signs is conducive to the differential diagnosis and the improvement of the diagnostic accuracy.

HRCT features between lepidic-predominant type and other pathological subtypes in early-stage invasive pulmonary adenocarcinoma appearing as a ground-glass nodule.

BACKGROUND: Different pathological subtypes of invasive pulmonary adenocarcinoma (IPA) have different surgical methods and heterogeneous prognosis. It is essential to clarify IPA subtypes before operation and high-resolution computed tomography (HRCT) plays a very important role in this regard. We aimed to investigate the HRCT features of lepidic-predominant type and other pathological subtypes of early-stage (T1N0M0) IPA appearing as a ground-glass nodule (GGN). METHODS: We performed a retrospective analysis on clinical data and HRCT features of 630 lesions in 589 patients with pathologically confirmed IPA (invasive foci > 5 mm) appearing as pure GGN (pGGN) and mixed GGN (mGGN) with consolidation-to-tumor ratio (CTR) ≤0.5 from January to December 2019. All GGNs were classified as lepidic-predominant adenocarcinoma (LPA) and nonlepidic-predominant adenocarcinoma (n-LPA) groups. Univariate analysis was performed to analyze the differences of clinical data and HRCT features between the LPA and n-LPA groups. Multivariate analysis was conducted to determine the variables to distinguish the LPA from n-LPA group independently. The diagnostic performance of different parameters was compared using receiver operating characteristic curves. RESULTS: In total, 367 GGNs in the LPA group and 263 GGNs in the n-LPA group were identified. In the univariate analysis, the CTR, mean CT values, and mean diameters as well as mixed GGN, deep lobulation, spiculation, vascular change, bronchial change, and tumor-lung interface were smaller in the LPA group than in the n-LPA group (P <  0.05). Logistic regression model was reconstructed including the mean CT value, CTR, deep lobulation, spiculation, vascular change, and bronchial change (P <  0.05). Area under the curve of the logistic regression model for differentiating LPA and n-LPA was 0.840 (76.4% sensitivity, 78.7% specificity), which was significantly higher than that of the mean CT value or CTR. CONCLUSIONS: Deep lobulation, spiculation, vascular change, and bronchial change, CT value > - 472.5 HU and CTR > 27.4% may indicate nonlepidic predominant invasive pulmonary adenocarcinoma in GGNs.

Pulmonary mucosa-associated lymphoid tissue lymphoma: CT findings and pathological basis.

BACKGROUND: Pulmonary mucosa-associated lymphoid tissue lymphoma (MALToma) is the most frequent subset of primary pulmonary lymphoma. This study aimed to identify radiologic characteristics of pulmonary MALToma based on computed tomography (CT) observations and pathologic features, and further investigate its prognosis. METHODS: Sixty-six patients (55.4 ± 10.9 years; 51.5% male) diagnosed as pulmonary MALToma by pathology were retrospectively enrolled. According to distributions and features of lesions shown on CT, patients were divided into three patterns, including single nodular/mass, multiple nodular/mass, and pneumonia-like consolidative. RESULTS: Variety of the location and extent of the lymphomatous infiltration accounted for different characteristics demonstrated at CT. The pneumonia-like consolidative pattern was the most frequent pattern observed in 42 patients (63.6%), followed by single nodular/mass (21.2%) and multiple nodular/mass (15.2%). CT features included air bronchogram (72.7%), well-marginated halo sign (53.0%), coarse spiculate with different lengths (72.7%), angiogram sign (77.1% of 35 patients), peribronchovascular thickening (48.5%), irregular cavitation (16.7%) and pulmonary cyst (7.6%). The estimated 5-year cumulative overall survival rate of pulmonary MALToma was 100.0%. CONCLUSIONS: Pulmonary MALToma demonstrates several characteristics at CT. Identification of the significant pulmonary abnormalities of this indolent disease entity might be helpful for early diagnosis and optimal treatment.

[Prediction of Pathological Subtypes of Lung Adenocarcinoma with Pure Ground Glass Nodules by Deep Learning Model].

Objective To make a preliminary pathological classification of lung adenocarcinoma with pure ground glass nodules(pGGN)on CT by using a deep learning model. Methods CT images and pathological data of 219 patients(240 lesions in total)with pGGN on CT and pathologically confirmed adenocarcinoma were collected.According to pathological subtypes,the lesions were divided into non-invasive lung adenocarcinoma group(which included atypical adenomatous hyperplasia and adenocarcinoma in situ and micro-invasive adenocarcinoma)and invasive lung adenocarcinoma group.First,the lesions were outlined and labeled by two young radiologists,and then the labeled data were randomly divided into two datasets:the training set(80%)and the test set(20%).The prediction Results of deep learning were compared with those of two experienced radiologists by using the test dataset. Results The deep learning model achieved high performance in predicting the pathological types(non-invasive and invasive)of pGGN lung adenocarcinoma.The accuracy rate in pGGN diagnosis was 0.8330(95% CI=0.7016-0.9157)for of deep learning model,0.5000(95% CI=0.3639-0.6361)for expert 1,0.5625(95% CI=0.4227-0.6931)for expert 2,and 0.5417(95% CI=0.4029-0.6743)for both two experts.Thus,the accuracy of the deep learning model was significantly higher than those of the experienced radiologists(P=0.002).The intra-observer agreements were good(Kappa values:0.939 and 0.799,respectively).The inter-observer agreement was general(Kappa value:0.667)(P=0.000). Conclusion The deep learning model showed better performance in predicting the pathological types of pGGN lung adenocarcinoma compared with experienced radiologists.

CT Characteristics and Pathologic Basis of Solitary Cystic Lung Cancer.

There are increasing reports of a type of lung cancer that manifests as solitary cystic airspaces. The purpose of this case series was to identify the CT features and possible mechanisms of solitary cystic lung cancer, on the basis of CT observations and pathologic characteristics. The clinical, imaging, and pathologic data of 106 patients with solitary cystic lung cancer were collected and analyzed between January 2011 and December 2017. CT images were reviewed independently by three radiologists who were blinded to pathologic findings. Demographic data and clinical and smoking status were extracted from the medical records. The mean age was 58.8 years 6 10.6 (standard deviation) (range, 30­82 years). CT features in the 106 patients included nonuniform cystic walls in 96 (90.6%) patients, cyst septations in 62 (58.5%) patients, nodular walls in 58 (54.7%) patients, ground-glass opacity around the cyst in 53 patients (50.0%), and irregular margins in 42 (39.6%) patients. At histologic examination, the majority of cases (81 [87.1%] of 93) were adenocarcinoma.

CT and histopathologic characteristics of lung adenocarcinoma with pure ground-glass nodules 10 mm or less in diameter.

OBJECTIVE: To evaluate CT and histopathologic features of lung adenocarcinoma with pure ground-glass nodule (pGGN) ≤10 mm in diameter. METHODS: CT appearances of 148 patients (150 lesions) who underwent curative resection of lung adenocarcinoma with pGGN ≤10 mm (25 atypical adenomatous hyperplasias, 42 adenocarcinoma in situs, 38 minimally invasive adenocarcinomas, and 45 invasive pulmonary adenocarcinomas) were analyzed for lesion size, density, bubble-like sign, air bronchogram, vessel changes, margin, and tumour-lung interface. CT characteristics were compared among different histopathologic subtypes. Univariate and multivariate analysis were used to assess the relationship between CT characteristics of pGGN and lesion invasiveness, respectively. RESULTS: There were statistically significant differences among histopathologic subtypes in lesion size, vessel changes, and tumour-lung interface (P<0.05). Univariate analysis revealed significant differences of vessel changes, margin and tumour-lung interface between preinvasive and invasive lesions (P<0.05). Logistic regression analysis showed that the vessel changes, unsmooth margin and clear tumour-lung interface were significant predictive factors for lesion invasiveness, with odds ratios (95% CI) of 2.57 (1.17-5.62), 1.83 (1.25-2.68) and 4.25 (1.78-10.14), respectively. CONCLUSION: Invasive lesions are found in 55.3% of subcentimeter pGGNs in our cohort. Vessel changes, unsmooth margin, and clear lung-tumour interface may indicate the invasiveness of lung adenocarcinoma with subcentimeter pGGN. KEY POINTS: • Invasive lesions were found in 55.3% of lung adenocarcinomas with subcentimeter pGGNs • Lesion size, vessel changes, and tumour-lung interface showed different among histopathologic subtypes • Vessel changes, unsmooth margin and clear tumour-lung interface were predictors for lesion invasiveness.

Value of Multi-detector CT in Detection of Isolated Spontaneous Superior Mesenteric Artery Dissection.

Objective To investigate the role of multi-detector computed tomography (CT) in the diagnosis and classification of isolated spontaneous superior mesenteric artery dissection (ISSMAD). Methods From July 2012 to December 2016, 30 consecutive patients with ISSMAD underwent CT scan at least two times. We retrospectively summarized the clinical characteristics and CT findings of them. The stenosis ratio of true lumen was compared between the patients without bowel ischemia and ones with bowel ischemia. Results There were 5 cases of type I ISSMAD, 14 cases of type 2, 1 case of type 3, 7 cases of type 4 and 3 cases of type V. Intestinal ischemia occurred in 5 patients. The stenosis ratio of true lumen in the patients without bowel ischemia was lower than that with bowel ischemia (45.6% vs. 76.0%, t=-14.5, P=0.000). Five patients with intestinal ischemia underwent superior mesenteric artery stenting and others received conservative therapy. The abdominal pain was alleviated for all the patients after treatment. Follow-up was complete in 30 cases. Follow-up CT angiography of superior mesenteric artery showed dissection remodeling in 12 patients. Conclusion Multi-detector CT is a valuable method in diagnosis and classification of ISSMAD and monitoring the changes of dissection.

[Correlations between Vessel Changes and the Histopathologic Subtypes of Lung Adenocarcinoma with Pure Ground-glass Nodule on Computed Tomography].

OBJECTIVE: To investigate the correlations between vessel changes and the histopathologic subtypes of lung adenocarcinoma with pure ground-glass nodule (pGGN) on computed tomography (CT). METHODS: Totally 107 patients (116 lesions) with lung adenocarcinomas with pGGN who had undergone curative resection were included. Vessel changes included vascular convergence and/or vessel dilation or distortion within the pGGN. According to the vessel appearances within the pGGN, all patients were categorized into two groups: no change group and change group. Pearson chi-square test was used to analyze the relationships between vessel changes and histopathologic subtypes. Mann-Whitney rank test and t-test were used to identify the relationship of vessels changes with pGGN density and diameter. RESULTS: Among these 116 pGGNs, there were 21 without vessel changes and 4 with vessel changes in 25 preinvasive lesions; 14 without vessel changes and 15 with vessel changes in 29 minimally invasive adenocacinomas; 16 without vessel changes and 46 with vessel changes in 62 invasive lung adenocarcinomas. There were statistically significant differences of vessel changes (P=0.000) among histopathologic subtypes. The lesion diameter was significantly different between these two groups (P=0.000), while the lesion density showed no significant difference (P=0.826). CONCLUSION: Vessel changes may indicate the invasiveness of lung adenocarcinoma with pGGNs and are related with the lesion diameter.

Value of Baseline Clinical and CT Characteristics for Predicting the Progression of Persistent Pure Ground-glass Nodule 10 mm or Less in Diameter.

Objective To explore the risk factors of the progression of persistent pure ground-glass nodule (pGGN) and make the risk stratification for pGGN 10 mm or less in diameter. Methods From June 2008 to April 2015,100 patients (108 lesions) with persistent pGGN≤10 mm in diameter were included in this study. Patients were followed up at least 1 year using thin-section computed tomography (CT). Patients' baseline clinical data and CT characteristics of pGGN were compared between progression group (size increased or/and solid component appeared) and non-progression group. Cox regression analysis was used to assess the relationship between clinical data,CT characteristics of pGGN,and lesion progression. The risk indices of lesion progression were calculated according to the results of Cox regression analysis and the relative factors of lung adenocarcinoma in previous studies. Logistic regression analysis was used to assess the relationship between risk indices and lesion progression. The optimal cutoff value was decided on receiver operating characteristic curve of risk indices and verified for predicting lesion progression. Results Fifteen of 108 lesions showed progression. The mean follow-up duration was (1016.36±486.00) days. There were statistically significant differences of lesion size,air bronchogram,and vessel changes between progression group and non-progression group (P=0.040,P=0.003,P=0.030,respectively).Lesion density (CT value≥-542.5 HU) and air bronchogram were the risk factors of lesion progression (P=0.003,P=0.021,respectively). The optimal cutoff value of total risk indices on predicting lesion progression was 4.25,with the sensitivity of 46.7%,specificity of 89.2%,and consistency of 83.3%. Conclusions CT value ≥-542.5 HU of pGGN and air bronchogram within lesion may predict lesion progression in persistent pGGN 10 mm or less in diameter. A risk index of less than 4.25 often suggests small probability of disease progression and thus a longer follow-up interval is recommended.

CT characteristics and pathological implications of early stage (T1N0M0) lung adenocarcinoma with pure ground-glass opacity.

OBJECTIVES: To analyze the CT characteristics and pathological classification of early lung adenocarcinoma (T1N0M0) with pure ground-glass opacity (pGGO). METHODS: Ninety-four lesions with pGGO on CT in 88 patients with T1N0M0 lung adenocarcinoma were selected from January 2010 to December 2012. All lesions were confirmed by pathology. CT appearances were analyzed including lesion location, size, density, uniformity, shape, margin, tumour-lung interface, internal and surrounding malignant signs. Lesion size and density were compared using analysis of variance, lesion size also assessed using ROC curves. Gender of patients, lesion location and CT appearances were compared using χ²-test. RESULTS: There were no significant differences in gender, lesion location and density with histological invasiveness (P > 0.05). The ROC curve showed that the possibility of invasive lesion was 88.73% when diameter of lesion was more than 10.5 mm. There was a significant difference between lesion uniformity and histological invasiveness (P = 0.01). There were significant differences in margin, tumour-lung interface, air bronchogram with histological invasiveness ( P = 0.02,P = 0.00,P = 0.048). The correlation index of lesion size and uniformity was r = 0.45 (P = 0.00). CONCLUSIONS: The lesion size and uniformity, tumour-lung interface and the air bronchogram can help predict invasive extent of early stage lung adenocarcinoma with pGGO. KEY POINTS: • CT characteristics and pathological classification of pGGO lung adenocarcinoma smaller than 3 cm • The optimal cut-off value for discriminating preinvasive from invasive lesions was 10.5 mm • Uniformity was significant difference between histological subtypes and correlated with lesion size • Tumour margin, tumour-lung interface and air bronchogram showed different between histological types • No significant difference in gender, lesion location and density with histological subtypes.

Correlations between pathologic subtypes/immunohistochemical implication and CT characteristics of lung adenocarcinoma ≤ 1 cm with ground-glass opacity.

OBJECTIVE: To discuss the correlation of pathologic subtypes and immunohistochemical implication with CT features of lung adenocarcinoma 1 cm or less in diameter with focal ground-glass opacity (fGGO). METHODS: CT appearances of 59 patients who underwent curative resection of lung adenocarcinoma ≤ 1 cm with fGGO were analyzed in terms of lesion location, size, density, shape (round, oval, polygonal, irregular), margin (smooth, lobular, spiculated, lobular and spiculated), bubble-like sign, air bronchogram, pleural tag, and tumor-lung interface. Histopathologic subtypes were classified according to International Association for the Study of Lung Cancer/ American Thoracic Society/European Respiratory Society classification of lung adenocarcinoma. Common molecular markers in immunohistochemical study included human epidermal growth factor receptor (HER)-1,HER-2,Ki-67, vascular endothelial growth factor (VEGF) and DNA topoisomerase 2Α.Patients' age and lesions' size and density were compared with pathologic subtypes using analysis of variance or nonparametric Wilcoxon tests. Patients' gender, lesion location, shape and margin, bubble-like sign, air bronchogram, pleural tag, and tumor-lung interface were compared with histopathologic subtypes and immunohistochemical implication using ψ² test or Fisher's exact test. RESULTS: The patients' gender, age, lesion location, shape, air bronchogram, pleural tag, and tumor-lung interface were not significantly different among different histopathologic subtypes (P=0.194, 0.126, 0.609, 0.678, 0.091, 0.374, and 0.339, respectively), whereas the lesion size,density,bubble-like sign, and margin showed significant differences (P=0.028, 0.002, 0.003, 0.046, respectively). The expression of Ki-67 significantly differed among nodules with different shapes(P=0.015). Statistically significant difference also existed between tumor-lung interface and HER-1 expression (P=0.019) and between bubble sign and HER-2 expression (P=0.049). CONCLUSIONS: Of lung adenocarcinoma ≤ 1 cm with fGGO,bubble-like sign occurs more frequently in invasive pulmonary adenocarcinoma and less frequently in atypical adenomatous hyperplasia. In addition, preinvasive lesions (atypical adenomatous hyperplasia and adenocarcinoma in situ) more frequently demonstrates smooth margin,while invasive lesions (minimally invasive adenocarcinoma and invasive pulmonary adenocarcinoma) more frequently demonstrates lobular and spiculated margin. Some CT features are associated with immunohistochemical implication of lung adenocarcinoma ≤ 1 cm with fGGO.

Comparative long-term prognosis of early surgery and surgery after surveillance for patients with ground-glass nodule adenocarcinomas.

To compare the pathological results and long-term survival results of early surgery and surgery after at least one year follow-up for ground-glass component predominant lung adenocarcinoma patients. From January 1, 2013 to August 31, 2017, a total of 279 patients with ground-glass nodules (GGNs) undergoing surgical resection and pathologically proved to be pulmonary adenocarcinoma were included in this study. All patients were divided into early surgery group (ES Group) (210 cases) and surgery after follow-up group (FS Group) (69 cases). Patients in FS group experienced at least one year surveillance. Clinical and imaging features were analyzed by using univariate analysis. After analysis, there was no statistical difference in pathological results and long-term prognosis between the two groups. In the follow-up group, grown GGNs have proved to have more aggressive pathological results. The one-year follow-up may be a feasible management method for patients with ground-glass component predominant GGN.

Nomogram model for the diagnosis of solitary nodular pulmonary mucinous adenocarcinoma.

The objective of this study was to develop a nomogram model based on the natural progression of tumor and other radiological features to discriminate between solitary nodular pulmonary mucinous adenocarcinoma and non-mucinous adenocarcinomas. A retrospective analysis was conducted on 15,655 cases of lung adenocarcinoma diagnosed at our institution between January 2010 and June 2023. Primary nodular invasive mucinous adenocarcinomas and non-mucinous adenocarcinomas with at least two preoperative CT scans were included. These patients were randomly assigned to training and validation sets. Univariate and multivariate analyses were employed to compare tumor growth rates and clinical radiological characteristics between the two groups in the training set. A nomogram model was constructed based on the results of multivariate analysis. The diagnostic value of the model was evaluated in both the training and validation sets using calibration curves and receiver operating characteristic curves (ROC). The study included 174 patients, with 58 cases of mucinous adenocarcinoma and 116 cases of non-mucinous adenocarcinoma. The nomogram model incorporated the maximum tumor diameter, the consolidation/tumor ratio (CTR), and the specific growth rate (SGR) to generate individual scores for each patient, which were then accumulated to obtain a total score indicative of the likelihood of developing mucinous or non-mucinous adenocarcinoma. The model demonstrated excellent discriminative ability with an area under the receiver operating characteristic curve of 0.784 for the training set and 0.833 for the testing set. The nomogram model developed in this study, integrating SGR with other radiological and clinical parameters, provides a valuable and accurate tool for differentiating between solitary nodular pulmonary mucinous adenocarcinoma and non-mucinous adenocarcinomas. This prognostic model offers a robust and objective basis for personalized management of patients with pulmonary adenocarcinomas.

Deep learning model based on primary tumor to predict lymph node status in clinical stage IA lung adenocarcinoma: a multicenter study.

Objective: To develop a deep learning model to predict lymph node (LN) status in clinical stage IA lung adenocarcinoma patients. Methods: This diagnostic study included 1,009 patients with pathologically confirmed clinical stage T1N0M0 lung adenocarcinoma from two independent datasets (699 from Cancer Hospital of Chinese Academy of Medical Sciences and 310 from PLA General Hospital) between January 2005 and December 2019. The Cancer Hospital dataset was randomly split into a training cohort (559 patients) and a validation cohort (140 patients) to train and tune a deep learning model based on a deep residual network (ResNet). The PLA Hospital dataset was used as a testing cohort to evaluate the generalization ability of the model. Thoracic radiologists manually segmented tumors and interpreted high-resolution computed tomography (HRCT) features for the model. The predictive performance was assessed by area under the curves (AUCs), accuracy, precision, recall, and F1 score. Subgroup analysis was performed to evaluate the potential bias of the study population. Results: A total of 1,009 patients were included in this study; 409 (40.5%) were male and 600 (59.5%) were female. The median age was 57.0 years (inter-quartile range, IQR: 50.0-64.0). The deep learning model achieved AUCs of 0.906 (95% CI: 0.873-0.938) and 0.893 (95% CI: 0.857-0.930) for predicting pN0 disease in the testing cohort and a non-pure ground glass nodule (non-pGGN) testing cohort, respectively. No significant difference was detected between the testing cohort and the non-pGGN testing cohort (P = 0.622). The precisions of this model for predicting pN0 disease were 0.979 (95% CI: 0.963-0.995) and 0.983 (95% CI: 0.967-0.998) in the testing cohort and the non-pGGN testing cohort, respectively. The deep learning model achieved AUCs of 0.848 (95% CI: 0.798-0.898) and 0.831 (95% CI: 0.776-0.887) for predicting pN2 disease in the testing cohort and the non-pGGN testing cohort, respectively. No significant difference was detected between the testing cohort and the non-pGGN testing cohort (P = 0.657). The recalls of this model for predicting pN2 disease were 0.903 (95% CI: 0.870-0.936) and 0.931 (95% CI: 0.901-0.961) in the testing cohort and the non-pGGN testing cohort, respectively. Conclusions: The superior performance of the deep learning model will help to target the extension of lymph node dissection and reduce the ineffective lymph node dissection in early-stage lung adenocarcinoma patients.

Classification of human coronary atherosclerotic plaques using ex vivo high-resolution multicontrast-weighted MRI compared with histopathology.

OBJECTIVE: The objective of our study was to evaluate the feasibility of ex vivo high-resolution multicontrast-weighted MRI to accurately classify human coronary atherosclerotic plaques according to the American Heart Association classification. MATERIALS AND METHODS: Thirteen human cadaver heart specimens were imaged using high-resolution multicontrast-weighted MR technique (T1-weighted, proton density-weighted, and T2-weighted). All MR images were matched with histopathologic sections according to the landmark of the bifurcation of the left main coronary artery. The sensitivity and specificity of MRI for the classification of plaques were determined, and Cohen's kappa analysis was applied to evaluate the agreement between MRI and histopathology in the classification of atherosclerotic plaques. RESULTS: One hundred eleven MR cross-sectional images obtained perpendicular to the long axis of the proximal left anterior descending artery were successfully matched with the histopathologic sections. For the classification of plaques, the sensitivity and specificity of MRI were as follows: type I-II (near normal), 60% and 100%; type III (focal lipid pool), 80% and 100%; type IV-V (lipid, necrosis, fibrosis), 96.2% and 88.2%; type VI (hemorrhage), 100% and 99.0%; type VII (calcification), 93% and 100%; and type VIII (fibrosis without lipid core), 100% and 99.1%, respectively. Isointensity, which indicates lipid composition on histopathology, was detected on MRI in 48.8% of calcified plaques. Agreement between MRI and histopathology for plaque classification was 0.86 (p < 0.001). CONCLUSION: Ex vivo high-resolution multicontrast-weighted MRI can accurately classify advanced atherosclerotic plaques in human coronary arteries.

[CT characteristics of primary salivary gland-type lung cancer].

OBJECTIVE: To improve the diagnostic accuracy of primary salivary gland-type lung cancer on CT. METHODS: The CT findings of 13 pathologically proven primary salivary gland-type lung cancers (mucoepidermoid carcinoma, n = 8, adenoid cystic carcinoma, n = 5) were retrospectively analyzed. RESULTS: Three mucoepidermoid carcinomas were located in the main bronchus, 4 in segmental bronchus, and 1 in peripheral lung. Intrabronchial nodule or mass with smooth or lobulated margin and punctuate or strip calcification (n = 2) was the main CT feature. The tumor showed moderate to significant enhancement after the administration of contrast medium. Three adenoid cystic carcinomas involved trachea, and 2 involved the main and lobular bronchi. The main CT features were diffuse or circumferential irregular thickness of the wall, distorted lumen, and nodule protruding into the lumen, and the longitudinal extent of the tumor was greater than its transverse axis. CONCLUSION: The CT findings of primary salivary gland-type lung cancer are rather specific and may provide helpful information for the clinical diagnosis and treatment.

The Use of CT Perfusion to Determine Microvessel Density in Lung Cancer: Comparison with FDG-PET and Pathology.

OBJECTIVE: To investigate the validity of CT perfusion in assessing angiogenic activity of lung cancer. METHODS: Fifty-six patients with lung cancer scheduled for elective surgical resection received 16-slice helical CT perfusion imaging. Time-density curve (TDC), blood flow (BF), blood volume (BV), mean transmit time (MTT) and permeability surface area product (PS) were calculated. 18F-deoxyglucose-positron emission tomography (FGD-PET) was carried out in 14 out of the 56 patients to calculate standardized uptake values (SUVs). Tumor microvessel density (MVD) was examined using CD34 immunohistochemical staining of the resected tumor tissue. Pearson's correlation analysis was used to evaluate potential correlation between CT perfusion parameters and MVD or SUV. RESULTS: Average time to peak height (TPH) of the TDCs (including two types of TDC) was 24.38±5.69 seconds. Average BF, BV, MTT and PS were 93.42±53.45 ml/100g/min,93.42±53.45 ml/100g,6.83±4.51 s and 31.92±18.73 ml/100g/min, respectively. Average MVD was 62.04±29.06/HPF. The mean SUV was 6.33±3.26. BF was positively correlated with MVD (r=0.620,P<0.01) and SUV (r=0.891, P<0.01). PS was also positively correlated with SUV (r=0.720, P<0.05). A positive correlation was also observed between tumor MVD and SUV (r=0.915, P<0.01). CONCLUSIONS: CT perfusion imaging is a reliable tool to evaluate the tumor neovascularity of lung cancer.

Comparative study of primary pulmonary cryptococcosis with multiple nodules or masses by CT and pathology.

The manifestations of pulmonary cryptococcosis with multiple nodules or masses on computed tomography (CT) are diverse and difficult to differentiate from those of lung cancer and pulmonary tuberculosis. The present study compared the multislice spiral CT signs with pathological results and used the pathological results to explain the CT signs with the aim of improving the accuracy of the diagnosis of this disease. A retrospective analysis of 20 patients with primary pulmonary cryptococcosis with multiple nodules or masses was performed. Based on the CT signs, eight patients had been misdiagnosed with lung cancer accompanied by intrapulmonary metastasis andthree patients had been misdiagnosed with tuberculosis. The major CT manifestations were a cluster of nodules or masses located within 2 cm below the pleura and distributed along the bronchi. A total of nine patients had primary lesions with diameters of 1.1-2.0 cm and 12 patients had satellite lesions with diameters of 0.1-1.0 cm. Regarding treatment, 5 patients underwent surgical monotherapy, 12 patients underwent antifungal monotherapy and three patients received surgery in combination with antifungal therapy. HE staining indicated that Cryptococcus neoformans was engulfed by macrophages, which were surrounded by massive infiltrating lymphocytes and a large amount of fibrous tissue, which formed multinucleated macrophages or granulomas. Periodic acid-Schiff staining was positive and acid fast staining was negative. In conclusion, comparison of CT signs with the pathological manifestation of pulmonary cryptococcosis with multiple nodules or masses indicated that the pathological results may explain certain imaging signs. Combination of CT and pathological examination may provide a deeper understanding of this disease and improve the accuracy of its diagnosis.

Transcarotid artery endovascular reconstruction of the aortic arch by modified bifurcated stent graft for Stanford type A dissection.

A 40-year-old man with Stanford type B dissection underwent his first endovascular repair (EVAR) in April 2004 by Talent thoracic stent graft. He had an uncomplicated recovery and maintained good blood pressure control. However, a new retrograde dissection appeared in September 2004. The new dissection involved his aortic arch and ascending thoracic aorta to the opening of the coronary arteries. To reconstruct the aortic arch, bypasses between the right common carotid artery (RCCA), left common carotid artery and left subclavian artery were performed before endovascular repair. A modified bifurcated Talent stent graft was deployed from the RCCA to the ascending thoracic aorta with a long limb in the innominate artery and a short limb in the aortic arch. A further two pieces of graft were deployed via the common femoral artery. The ascending thoracic aorta and aortic arch were reconstructed completely by the bifurcated stent graft. The final angiography confirmed that there was good stent graft configuration, normal blood flow, and stable haemodynamics. No endoleak or other major complications were encountered. This result indicated that it is possible to reconstruct the aortic arch with a bifurcated stent graft and could be a new endovascular repair model for complex thoracic aortic aneurysm and dissection.

[Multi-slice computed tomography of myocardial bridge and mural coronary artery and clinical significance thereof].

OBJECTIVE: To investigate the diagnosis of myocardial bridge and mural coronary artery (MB-MCA) with multi-slice computed tomography (MSCT) and clinical significance thereof. METHODS: 900 patients suspected as with coronary artery disease (CHD) underwent 64-slice computed tomography performed by 3 radiologists independently. When consistency was obtained among the independent interpretations of the tomogram among them the diagnosis of MB-MCA could be confirmed. The length of MCA and thickness of MB were measured, and the situation of the nearby arteries were observed and recorded. Based on the above mentioned 3 items the reference scoring criteria were established. RESULTS: 180 sites of MB-NCA were found in 167 (18.56%) of the 900 patients, 112 males and 55 females, aged 54.46 (33 - 84). 167 of the 180 sites of MB-MCA were located on the LAD (92.7%). MCA could be covered by MB in a form of semi-circularity (63.89%, 115/180) or circularity (36.11%, 65/180) The length of MCA was 18.7 mm +/- 10.2 mm, and the thickness of MB was 1.7 mm +/- 1.2 mm. 70% of the arteries proximal and/or distal to the MB-MCA were tortuous. Length of MCA < 10 mm, half-surrounding of MB, and smoothness of the proximal and distant vessels were scored as 1; length of MCA of 10 approximately 20 mm, thickness of MB < 1 mm, and tortuousness of the unilateral proximal or distant vessel were scored as 2; and length of MCA > 20 mm, thickness of MB > 1 mm, and tortuousness of the bilateral proximal and distant vessels were scored as 3. Coronary atherosclerosis was found in 88 of the 167 patients (52.69%). No significant correlation was found between coronary atherosclerosis and MB-MCA grade (u = 1.234, P > 0.05). CONCLUSION: Sixty-four-slice CT can be used to confirm the presence of MB = MCA and the morphology of coronary artery with MB-MCA. Coronary atherosclerosis is not significantly correlated with MB-MCA grade.