[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.

[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 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 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.

[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.

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.

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.

Fatal interstitial lung disease after addition of sorafenib to a patient with lung adenocarcinoma who had failed to improve with erlotinib alone.

Interstitial lung disease (ILD) induced by epidermal growth factor receptor tyrosine kinase inhibitors has been extensively documented with decreasing incidence after appropriate patient selection due to increasing awareness over the years. However, ILD induced by sorafenib was mentioned with lower frequency only in patients with hepatocellular and renal cell carcinoma living in Japan but not in patients with other carcinomas or living outside Japan, and it has been overlooked in clinical practice. In the present case, sorafenib was added to the treatment of a 60-year-old non-smoking patient with non-small cell lung cancer (NSCLC). After his failing to improve with erlotinib alone, erlotinib was continued to be given in combination with sorafenib as a salvage therapy. Although clinical signs of ILD were observed 2 weeks after the addition of sorafenib, the radiological diagnosis of ILD was only made 41 days after the initiation of the combination treatment, and the patient died 56 days after treatment onset. It was concluded that ILD was indeed induced by sorafenib. This is the first report of ILD induced by sorafenib in a patient with NSCLC living outside Japan. Oncologists should be aware of this fatal complication for its early detection in order to avoid a severe course of ILD leading to a decrease in the ILD mortality rate.

[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.

Assessment of the anterior spinal artery and the artery of Adamkiewicz using multi-detector CT angiography.

BACKGROUND: Damage to the spinal cord after the treatment of the descending thoracic and thoracoabdominal aortic aneurysms is an uncommon but devastating complication. The artery of Adamkiewicz (AKA) is the principal arterial supply of the anterior spinal artery (ASA) in the lower thoracic and lumbar level. The purpose of this study was to evaluate the visualization of the anterior spinal artery and the artery of Adamkiewicz, the affecting factors for the detection rate using multi-detector row CT (MDCT). METHODS: Ninety-nine consecutive patients (31 women and 68 men; age range, 25 - 90 years; average age 61.3 years), with suspicion for thoracic aortic lesions necessitating surgical intervention (31 aortic aneurysm, 45 dissection, 5 intramural hematoma, and 18 normal), underwent CT angiography from the aortic arch to the aortic bifurcation. Transverse sections, multiplanar reformations and thin maximum intensity projections were used to assess the ASA and AKA. The level of the ASA and AKA origins and CT acquisition parameters were recorded. The contrast-to-noise ratio of the image, an index of the mass of the T11 body (vertebral mass index), the subcutaneous fat thickness, and the CT value within the aortic arch and at the T11 level were measured. The detection of the ASA and AKA were evaluated relative to the acquisition parameters, scan characteristics, and aortic lesion type. Differences were assessed with the Wilcoxon rank-sum and t tests. RESULTS: The ASA was visualized in 51 patients (52%) and the AKA in 18 patients (18%). The ASA was identified in 36/67 patients (54%) with 1.25 mm thickness and in 15/32 patients (47%) with 2.5 - 3.0 mm thickness. This difference did not achieve significance (P = 0.13). The detection rate of the ASA and the AKA was influenced by the vertebral mass index and the contrast-to-noise ratio (P < 0.05). The amount of subcutaneous fat affected the detection rate of the ASA (P < 0.05) but not the AKA. In CT scans of ASA detection, the mean CT values in the aorta at the arch and at T11 were 360 and 358 HU, respectively, whereas in CT scans without ASA detection, the CT values in the aorta at the arch and at T11 were lower (P < 0.05), 297 and 317 HU, respectively. CONCLUSIONS: The ASA and AKA were less frequently detected in our cohort than previous reports. The visualization of the ASA and AKA was significantly affected by aortic enhancement, the "vertebral mass index", and the contrast-to-noise ratio.

[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.