Bronchial Artery Angiogenesis Drives Lung Tumor Growth

Role of drug-eluting bead bronchial arterial chemoembolisation in the treatment of non-small cell lung cancer: protocol for a meta-analysis

BACKGROUND

Non-small cell lung cancer (NSCLC) has a poor prognosis. Transvascular intervention is an important approach for treating NSCLC. Drug-eluting bead bronchial artery chemoembolisation (DEB-BACE) is a technique of using DEBs loaded with chemotherapeutic drugs for BACE. This study aims to conduct a meta-analysis to comprehensively assess the effectiveness and safety of DEB-BACE in treating NSCLC and investigate a novel therapeutic strategy for NSCLC.

METHODS AND ANALYSIS

Wanfang, China National Knowledge Infrastructure, Medline (via PubMed), Cochrane Library, Scopus and Embase databases will be searched in November 2024. A meta-analysis will be conducted to assess the effectiveness and safety of DEB-BACE in the treatment of NSCLC. The following keywords will be applied: "Carcinoma, Non-Small-Cell Lung", "Non-Small Cell Lung Cancer", "Drug-Eluting Bead Bronchial Arterial Chemoembolization" and "drug-eluting beads". Reports in Chinese or English comparing the efficacy of DEB-BACE with other NSCLC treatment options will be included. Case reports, single-arm studies, conference papers, abstracts without full text and reports published in languages other than English and Chinese will not be considered. The Cochrane Handbook for Systematic Reviews of Interventions will be used to independently assess the risk of bias for each included study. In case of significant heterogeneity between studies, possible sources of heterogeneity will be explored through subgroup and sensitivity analysis. For the statistical analysis of the data, RevMan V.5.3 will be used.

ETHICS AND DISSEMINATION

This meta-analysis will seek publication in a peer-reviewed journal on completion. Ethical approval is not required for this study as it is a database-based study.

PROSPERO REGISTRATION NUMBER

CRD42023411392.

The Value of Contrast-Enhanced Ultrasound (CEUS) in the Evaluation of Central Lung Cancer with Obstructive Atelectasis

Purpose: To assess the diagnostic performance of contrast-enhanced ultrasound (CEUS) alongside contrast-enhanced computed tomography (CECT) in evaluating central lung cancer (CLC). Materials and Methods: From 2006 to 2022, 54 patients with CLC and obstructive atelectasis (OAT) underwent standardized examinations using CEUS in addition to CECT. The ability to differentiate CLC from atelectatic tissue in CECT and CEUS was categorized as distinguishable or indistinguishable. In CEUS, in distinguishable cases, the order of enhancement (time to enhancement) (OE; categorized as either an early pulmonary arterial [PA] pattern or a delayed bronchial arterial [BA] pattern of enhancement), the extent of enhancement (EE; marked or reduced), the homogeneity of enhancement (HE; homogeneous or inhomogeneous), and the decrease in enhancement (DE; rapid washout [<120 s] or late washout [≥120 s]) were evaluated. Results: The additional use of CEUS improved the diagnostic capability of CECT from 75.9% to 92.6% in differentiating a CLC from atelectatic tissue. The majority of CLC cases exhibited a BA pattern of enhancement (89.6%), an isoechoic reduced enhancement (91.7%), and a homogeneous enhancement (91.7%). Rapid DE was observed in 79.2% of cases. Conclusions: In cases of suspected CLC with obstructive atelectasis, the application of CEUS can be helpful in differentiating tumor from atelectatic tissue and in evaluating CLC.

Effect of angiogenesis inhibitors on wound healing in patients with ovarian cancer: A meta-analysis

Angiogenic inhibitors have been demonstrated to inhibit tumour cells in ovarian carcinoma, but the initial data are not accurate enough to indicate the influence of these drugs on the post-therapy wound healing. In order to assess the effect of angiogenic inhibitors on the treatment of wound healing in ovarian carcinoma, we performed a meta-analysis of related literature. For this meta-analysis, we looked up the data from 4 databases: PubMed, EMBASE, Web of Science and the Cochrane Library. All literature searches were performed up to October 2023. The ROBINS-I tool was applied to evaluate the risk of bias in the inclusion trials, and statistical analysis was performed with RevMan 5.3. In this research, 971 related research were chosen, and 9 of them were selected. These studies were published between 2013 and 2023. In all 9 trials, a total of 3902 patients were enrolled. There was a significant reduction in the risk of wound infection in the control group than in those who received angiogenesis inhibitors (OR, 0.66; 95% CI, 0.49-0.89 p = 0.007). The risk of developing an abscess was not significantly different from that of those who received angiogenesis inhibitors (OR, 0.80; 95% CI, 0.20-3.12 p = 0.74). The risk of perforation in the control group was smaller than that in those receiving angiogenic inhibitors (OR, 0.25; 95% CI, 0.11-0.56 p = 0.0006). There was a significant increase in the risk of injury and GI perforation in women who received angiogenic inhibitors than in the control group. But the incidence of abscess did not differ significantly among the two groups.

The Role of Contrast-Enhanced Ultrasound Plus Color Parametric Imaging in the Differential Diagnosis of Subpleural Pulmonary Lesions

OBJECTIVES

To distinguish benign and malignant subpleural pulmonary lesions (SPLs) with contrast-enhanced ultrasound (CEUS) and color parametric imaging (CPI), and evaluate the role of CEUS plus CPI in the differential diagnosis of pathological types of SPLs.

METHODS

One hundred and thirty-six patients underwent CEUS with a Logiq E9 XD Clear ultrasonic machine equipped with a 3.5- to 5.0-MHz C5-1 transducer in our center were enrolled in our study, including 27 cases of benign lesions and 109 cases of malignant lesions. The ultrasound contrast agent used in this study was SonoVue. CEUS images and CPI of all cases were reviewed and analyzed by the resident and staff radiologist groups separately.

RESULTS

With CEUS alone, by both the two groups, the main enhancement pattern of benign SPLs was arborization (P < .001), while centripetal enhancement pattern occurred more frequently in malignant SPLs (P < .001). With CEUS plus CPI, by both the two groups, the main enhancement pattern of benign SPLs was arborization (P < .001), while those of malignant SPLs were centripetal (P < .001) and eccentric (P < .05). The diagnosis performance of CEUS plus CPI was significantly higher than that of CEUS alone in both the resident (area under the curve [AUC] = 0.857 vs 0.677, P < .001) and staff (AUC = 0.866 vs 0.681, P < .001) groups. Moreover, CPI offered remarkable inter-consistency improvements in the enhancement pattern determination between the two groups.

CONCLUSION

The CEUS enhancement patterns would provide information of blood perfusion patterns in the differential diagnosis of benign and malignant SPLs. The diagnosis performance could be significantly improved by CEUS plus CPI compared with CEUS alone.

Drug-eluting beads bronchial arterial chemoembolization vs. conventional bronchial arterial chemoembolization in the treatment of advanced non-small cell lung cancer

Purpose

To compare the effectiveness and safety of drug-eluting bead bronchial artery chemoembolization (DEB-BACE) with conventional bronchial artery chemoembolization (cBACE) and provide a novel treatment option for advanced non-small cell lung cancer (NSCLC).

Methods

Patients with advanced NSCLC underwent DEB-BACE or cBACE and were screened retrospectively. Progression-free survival (PFS) and overall survival (OS) were the primary outcome indicators, while technical success rate, objective response rate (ORR), disease control rate (DCR), and adverse events (AEs) were the secondary ones.

Results

A total of 41 patients were enrolled in the study, 12 in the DEB-BACE group and 29 in the cBACE group, according to the treatment regimen. No patient achieved complete response. Eighteen patients achieved partial response (9 in each group), 15 patients achieved stable disease (3 in the DEB-BACE group and 12 in the cBACE group), and eight patients achieved progressive disease (all in the cBACE group) when treated for 2 months. The overall ORR and DCR were 43.9% (18/41) and 80.5% (33/41), respectively. ORR and DCR in the DEB-BACE group were 50.0% (9/12) and 100.0% (12/12), respectively, while ORR and DCR in the cBACE group were 31.0% (9/29) and 72.4% (21/29), respectively. Compared to cBACE, the ORR and DCR of DEB-BACE were significantly improved (p < 0.05). The median PFS was better in the DEB-BACE group than in the cBACE group (6.95 months vs. 3.20 months, respectively, Hazard Ratio [HR] = 0.416; p = 0.005). Furthermore, the median OS was significantly better in the DEB-BACE group than in the cBACE group (28.5 months vs. 22.5 months, respectively, HR = 0.316; p = 0.020).

Conclusion

DEB-BACE has a good safety and therapeutic profile in advanced NSCLC and is superior to cBACE. DEB-BACE can be used as an alternative treatment option for advanced NSCLC, even in elderly patients.

A combined non-enhanced CT radiomics and clinical variable machine learning model for differentiating benign and malignant sub-centimeter pulmonary solid nodules

BACKGROUND

Radiomics has been used to predict pulmonary nodule (PN) malignancy. However, most of the studies focused on pulmonary ground-glass nodules. The use of computed tomography (CT) radiomics in pulmonary solid nodules, particularly sub-centimeter solid nodules, is rare.

PURPOSE

This study aims to develop a radiomics model based on non-enhanced CT images that can distinguish between benign and malignant sub-centimeter pulmonary solid nodules (SPSNs, <1 cm).

METHODS

The clinical and CT data of 180 SPSNs confirmed by pathology were analyzed retrospectively. All SPSNs were divided into two groups: training set (n = 144) and testing set (n = 36). From non-enhanced chest CT images, over 1000 radiomics features were extracted. Radiomics feature selection was performed using the analysis of variance and principal component analysis. The selected radiomics features were fed into a support vector machine (SVM) to develop a radiomics model. The clinical and CT characteristics were used to develop a clinical model. Associating non-enhanced CT radiomics features with clinical factors were used to develop a combined model using SVM. The performance was evaluated using the area under the receiver-operating characteristic curve (AUC).

RESULTS

The radiomics model performed well in distinguishing between benign and malignant SPSNs, with an AUC of 0.913 (95% confidence interval [CI], 0.862-0.954) in the training set and an AUC of 0.877 (95% CI, 0.817-0.924) in the testing set. The combined model outperformed the clinical and radiomics models with an AUC of 0.940 (95% CI, 0.906-0.969) in the training set and an AUC of 0.903 (95% CI, 0.857-0.944) in the testing set.

CONCLUSIONS

Radiomics features based on non-enhanced CT images can be used to differentiate SPSNs. The combined model, which included radiomics and clinical factors, had the best discrimination power between benign and malignant SPSNs.

Contrast-Enhanced Ultrasound in Distinguishing between Malignant and Benign Peripheral Pulmonary Consolidations: The Debated Utility of the Contrast Enhancement Arrival Time

Background. Limited studies and observations conducted on a too small number of patients prevent determining the actual clinical utility of pulmonary contrast-enhanced ultrasound (CEUS). The aim of the present study was to examine the efficacy of contrast enhancement (CE) arrival time (AT) and other dynamic CEUS findings for differentiating between malignant and benign peripheral lung lesions. Methods. 317 inpatients and outpatients (215 men, 102 women; mean age: 52 years) with peripheral pulmonary lesions were included in the study and underwent pulmonary CEUS. Patients were examined in a sitting position after receiving an intravenous injection of 4.8 mL of sulfur hexafluoride microbubbles stabilized by a phospholipid shell as ultrasound contrast agent (SonoVue-Bracco; Milan, Italy). Each lesion was observed for at least 5 min in real-time and the following temporal characteristics of enhancement were detected: the arrival time (AT) of microbubbles in the target lesion; the enhancement pattern; the wash-out time (WOT) of microbubbles. Results were then compared in light of the definitive diagnosis of community acquired pneumonia (CAP) or malignancies, which was not known at the time of CEUS examination. All malignant cases were diagnosed by histological results, while pneumonia was diagnosed on the basis of clinical and radiological follow-up, laboratory findings and, in some cases, histology. Results. CE AT has not been shown to differ between benign and malignant peripheral pulmonary lesions. The overall diagnostic accuracy and sensibility of a CE AT cut-off value < 10 s in discriminating benign lesions were low (diagnostic accuracy: 47.6%; sensibility: 5.3%). Poor results were also obtained in the sub-analysis of small (mean diameter < 3 cm) and large (mean diameter > 3 cm) lesions. No differences were recorded in the type of CE pattern showed between benign and malignant peripheral pulmonary lesions. In benign lesions we observed a higher frequency of delayed CE wash-out time (WOT) > 300 s. Anyhow, a CE WOT cut-off value > 300 s showed low diagnostic accuracy (53.6%) and sensibility (16.5%) in discriminating between pneumonias and malignancies. Similar results were also obtained in the sub-analysis by lesion size. Squamous cell carcinomas showed a more delayed CE AT compared to other histopathology subtypes. However, such a difference was statistically significant with undifferentiated lung carcinomas. Conclusions. Due to an overlap of CEUS timings and patterns, dynamic CEUS parameters cannot effectively differentiate between benign and malignant peripheral pulmonary lesions. Chest CT remains the gold standard for lesion characterization and the eventual identification of other pneumonic non-subpleural localizations. Furthermore, in the case of malignancy, a chest CT is always needed for staging purposes.

Clinical outcomes of vinorelbine loading CalliSpheres beads in the treatment of previously treated advanced lung cancer with progressive refractory obstructive atelectasis

Background: Drug-eluting beads bronchial arterial chemoembolization (DEB-BACE) has been used in the treatment of locally advanced lung cancer and has the potential to improve outcomes and reduce recurrence. However, DEB-BACE shows a poor therapeutic effect in advanced lung cancer after failure of multiple therapies. This study assessed the effect of DEB-BACE in the treatment of progressive lung cancer with refractory obstructive atelectasis. Methods: Progressive advanced lung cancer patients with refractory obstructive atelectasis were voluntarily enrolled in this study after failure of multiple conventional therapies. Baseline information, DEB-BACE treatment process, and changes in clinical symptoms were recorded. The primary endpoints were the objective response rate (ORR) and improvement rate of dyspnea. The secondary endpoints were time-to-progression (TTP), overall survival (OS), and rate of pulmonary re-expansion. Treatment-related adverse events and serious adverse events were analyzed to assess the safety of DEB-BACE. The Cox regression model was performed to analyze the possible factors impacting prognosis of DEB-BACE. Results: DEB-BACE was successfully performed with CalliSpheres beads loaded with vinorelbine in the 20 enrolled patients. ORR and disease control rate were 80% and 85%, respectively, at the first follow-up (43.4 ± 15.26 days). The improvement rate of dyspnea was 85% and 80% at 1 week and 1 month (p < 0.0001, p < 0.0001), respectively. TTP was 41.25 ± 14.43 days and 89.55 ± 61.7 days before and after DEB-BACE, respectively; DEB-BACE delayed the progression of advanced lung cancer (p < 0.0001). OS was 238.03 ± 33.74 days (95% confidence interval: 171.9-304.16). The rate of pulmonary re-expansion was 80% at the first follow-up. The reasons for poor prognosis were tumor necrosis, longer disease duration, and pulmonary atelectasis duration (p = 0.012, p = 0.038, p = 0.029). Massive hemoptysis was observed in two cases, and one patient died of asphyxia caused by hemoptysis. Moderate hemoptysis occurred in one case. All three adverse events were considered as the result of the tumor cavity after DEB-BACE. Conclusion: DEB-BACE loaded with vinorelbine is a feasible option for progressive advanced lung cancer with obstructive atelectasis after failure of other treatments.

The Vasculature in Pulmonary Fibrosis

Purpose of Review

The current paradigm of idiopathic pulmonary fibrosis (IPF) pathogenesis involves recurrent injury to a sensitive alveolar epithelium followed by impaired repair responses marked by fibroblast activation and deposition of extracellular matrix. Multiple cell types are involved in this response with potential roles suggested by advances in single-cell RNA sequencing and lung developmental biology. Notably, recent work has better characterized the cell types present in the pulmonary endothelium and identified vascular changes in patients with IPF.

Recent Findings

Lung tissue from patients with IPF has been examined at single-cell resolution, revealing reductions in lung capillary cells and expansion of a population of vascular cells expressing markers associated with bronchial endothelium. In addition, pre-clinical models have demonstrated a fundamental role for aging and vascular permeability in the development of pulmonary fibrosis.

Summary

Mounting evidence suggests that the endothelium undergoes changes in the context of fibrosis, and these changes may contribute to the development and/or progression of pulmonary fibrosis. Additional studies will be needed to further define the functional role of these vascular changes.

Bronchial Artery Chemoembolization With Radiopaque Doxorubicin Eluding Beads in Patients With Malignant Hemoptysis from Metastatic Lung Cancer

Purpose:This pilot study was designed to assess the technical feasibility and safety of bronchial artery chemoembolization with radiopaque doxorubicin eluting beads (DEB-BACE) in patients with malignant hemoptysis from pulmonary metastasis. Materials & Methods: Four patients underwent DEB-BACE using 70-150 μm radiopaque DEB (LC Beads LUMI, Boston Scientific). Beads delivery and deposition were assessed under fluoroscopy and cone beam computed tomography (CT), respectively. Results: All 4 procedures were technically successful. Beads delivery and deposition were successfully visualized under fluoroscopy and cone beam CT guidance in all cases. Hemoptysis was resolved after embolization in all 4 patients. There were no adverse events or immediate or early complications after DEB-BACE. Two patients (50%) required repeat DEB-BACE within 1 week due to recurrent hemoptysis, and 1 patient had DEB-BACE 1.5 years later due to recurrent hemoptysis from the contralateral lung. All targeted lesions decreased in size in follow-up studies (mean 16 months, range 1-33 months). One patient died of progressive cancer disease invading the heart 1 month after DEB-BACE. Conclusions: DEB-BACE using radiopaque LC Beads LUMI loaded with doxorubicin is technically feasible and safe for controlling hemoptysis and cancer progression in patients with metastatic lung tumors. Visualization of beads delivery under fluoroscopy and deposition of beads under cone beam CT facilitate delivery of beads and embolization of bronchial arteries.

Contrast-enhanced ultrasound (CEUS) - A new tool for evaluating blood supply in primary peripheral lung cancer

OBJECTIVES

To explore the feasibility of contrast-enhanced ultrasound (CEUS) as a new tool for characterizing vascularization of primary peripheral lung cancer.

METHODS

315 consecutive patients with definite primary peripheral lung cancers underwent CEUS examination from November 2016 to March 2022. CEUS parameters including time to enhancement (TE), time to peak (TP), time to wash-out (TW), distribution of vessels (DV), extent of enhancement (EE) and homogeneity of enhancement (HE) were obtained.

RESULTS

The lesions were grouped on the basis of TE which reflects tumor vascularization: early enhancement (pulmonary arterial vascularization) (n = 91) and delayed enhancement group (bronchial arterial vascularization) (n = 224). Overall, lung tumors commonly (71.1%) manifested a delayed enhancement which indicating blood supply originated from bronchial arteries, while an early enhancement was present in less than a third of the cases. Tumors with bronchial vascularization tended to show a delayed, reduced and heterogeneous enhancement. Correspondingly, it is characterized by a shorter TE, marked EE and a relatively infrequent occurrence of necrosis in tumors with pulmonary vascularization.

CONCLUSIONS

Providing micro-perfusion information, CEUS is a potentially imaging tool for evaluating blood supply in primary peripheral lung cancer.

Comparison of the Value of Conventional Ultrasound and Contrast-Enhanced Ultrasound-Guided Puncture Biopsy in Different Sizes of Peripheral Pulmonary Lesions

Objective

To compare the clinical value of contrast-enhanced ultrasound and conventional ultrasound-guided puncture biopsy in peripulmonary lesions of different sizes.

Materials and Methods

110 patients with peripulmonary lesions were randomly divided into two groups: the conventional ultrasound-guided group and the contrast-enhanced ultrasound-guided group. The lesions in the two groups were further divided into two groups according to the size of the lesions, and the tissues taken after puncture biopsy were sent for pathological examination. The pathological results were compared with the postoperative pathological results and other examination results, and the complications were recorded at the same time.

Results

In the conventional ultrasound group, the success rate of single puncture was 72.7% and the success rate of puncture was 80.0%; in the contrast group, the success rate of single puncture was 90.9% and the success rate of puncture was 94.6%. The difference between the two groups was statistically significant. There was no significant difference in needle bleeding and pneumothorax between the two groups. In the <30 mm group, there was no significant difference in the success rate of single puncture and the success rate of puncture between the two groups according to the size of the lesions. In the ≥30 mm group, the success rate of single puncture (97.1%) and puncture success rate (97.1%) in the contrast guidance group were higher than those in the conventional ultrasound guidance group (70.3%, 78.4%) and the difference was statistically significant (p < 0.05).

Conclusion

Compared with conventional ultrasound, for peripheral pulmonary lesions guided by contrast-enhanced ultrasonography, especially when the maximum diameter of the lesion is ≥ 30 mm, needle biopsy has better guiding significance; for peripheral lung lesions with a maximum diameter of <30 mm, contrast-enhanced ultrasonography is compared with conventional ultrasound guidance. The puncture success rate was not significantly different.

Perfusion Patterns of Peripheral Pulmonary Granulomatous Lesions Using Contrast-Enhanced Ultrasound (CEUS) and Their Correlation with Immunohistochemically Detected Vascularization Patterns

PURPOSE

To describe the perfusion patterns of peripheral pulmonary granulomatous lesions (PPGLs) by contrast-enhanced ultrasound (CEUS) and their correlation with vascularization patterns (VPs) represented by immunohistochemical (CD34) endothelial staining.

PATIENTS AND METHODS

From January 2007 until September 2020, 10 consecutive patients with histologically confirmed PPGLs were investigated by CEUS. The time to enhancement, classified as early pulmonary-arterial (PA) pattern of enhancement versus delayed bronchial-arterial (BA) pattern of enhancement, the extent of enhancement, classified as marked or reduced, the homogeneity of enhancement, classified as homogeneous or inhomogeneous, and the decrease of enhancement, classified as rapid washout (<120 seconds) or a late washout (≥120 seconds), were analyzed retrospectively. Furthermore, the tissue samples from the study patients and as a control group, 10 samples of normal lung tissue obtained by autopsy, and 10 samples of lung tissue with acute pneumonia obtained by autopsy were immunohistochemically stained with CD34 antibody. The presence of avascular areas (AAs) and the VPs were evaluated in all tissue samples.

RESULTS

On CEUS, all PPGLs showed a reduced inhomogeneous BA pattern of enhancement and a rapid washout (<120 seconds). On CD34 staining, all PPGLs showed central AAs in granulomas and a chaotic VP similar to angiogenesis in lung tumors. The lung tissue in control groups revealed on CD34 staining a regular alveolar VP.

CONCLUSION

The PPGLs on CEUS show an identical perfusion pattern similar to those of malignant lesions. Furthermore, for the first time, neoangiogenesis was demonstrated as a histopathological correlate to BA pattern of enhancement on CEUS.

Pulmonary Delivery of Theranostic Nanoclusters for Lung Cancer Ferroptosis with Enhanced Chemodynamic/Radiation Synergistic Therapy

Inefficient tumor accumulation and penetration remain as the main challenges to therapy efficacy of lung cancer. Local delivery of smart nanoclusters can increase drug penetration and provide superior antitumor effects than systemic routes. Here, we report self-assembled pH-sensitive superparamagnetic iron oxide nanoclusters (SPIONCs) that enhance in situ ferroptosis and apoptosis with radiotherapy and chemodynamic therapy. After pulmonary delivery in orthotopic lung cancer, SPIONCs disintegrate into smaller nanoparticles and release more iron ions in an acidic microenvironment. Under single-dose X-ray irradiation, endogenous superoxide dismutase converts superoxide radicals produced by mitochondria to hydrogen peroxide, which in turn generates hydroxyl radicals by the Fenton reaction from iron ions accumulated inside the tumor. Finally, irradiation and iron ions enhance tumor lipid peroxidation and induce cell apoptosis and ferroptosis. Thus, rationally designed pulmonary delivered nanoclusters provide a promising strategy for noninvasive imaging of lung cancer and synergistic therapy.

Role of Contrast-Enhanced Ultrasound in Pulmonary Lesions: 5-Year Experience at a Single Center

Contrast-enhanced ultrasound (CEUS) for the differentiation of benign and malignant peripheral pulmonary lesions has been considered experimental for many years. This study was aimed at evaluating the feasibility of CEUS as a diagnostic modality in this area of discussion. CEUS diagnostic accuracy was explored by comparison with contrast-enhanced computed tomography (CECT). The collective included 449 patients with 449 definitive diagnoses (benign, 178; malignant, 271). Logistic regression analysis of CEUS data revealed that delayed time to enhancement, chaotic pattern of distribution of vessels and mild extent of enhancement were independent risk factors for predicting malignancy. Time to wash-out and homogeneity of enhancement did not differ between the two groups (p > 0.05). Based on histopathology or clinical follow-up as a reference standard, CEUS and CECT had similar diagnostic accuracies of 80.16% and 81.75%, respectively. CEUS is a potentially useful imaging tool for diagnosing peripheral pulmonary lesions.

Strategies for Engineering Exosomes and Their Applications in Drug Delivery

Exosomes are representative of a promising vehicle for delivery of biomolecules. Despite their discovery nearly 40 years, knowledge of exosomes and extracellular vesicles (EVs) and the role they play in etiology of disease and normal cellular physiology remains in its infancy. EVs are produced in almost all cells, containing nucleic acids, lipids, and proteins delivered from donor cells to recipient cells. Consequently, they act as mediators of intercellular communication and molecular transfer. Recent studies have shown that, exosomes are associated with numerous physiological and pathological processes as a small subset of EVs, and they play a significant role in disease progression and treatment. In this review, we discuss several key questions: what are exosomes, why do they matter, and how do we repurpose them in their strategies and applications in drug delivery systems. In addition, opportunities and challenges of exosome-based theranostics are also described and directions for future research are presented.

Successful eight-year survival of unresectable lung adenocarcinoma with bronchial artery infusion chemotherapy: A case report

A case report of eight year complete remission post bronchial artery infusion (BAI) chemotherapy (Pimetrazine and cisplatin) for unresectable lung adenocarcinoma.

Perfusion Patterns of Peripheral Pulmonary Lesions in COVID-19 Patients Using Contrast-Enhanced Ultrasound (CEUS): A Case Series

PURPOSE

To describe perfusion patterns of peripheral pulmonary lesions (PPLs) in COVID-19 patients using contrast-enhanced ultrasound (CEUS).

PATIENTS AND METHODS

From April 2020 until July 2020, 11 consecutive patients with RT-PCR-confirmed COVID-19 and PPLs sized over 5 mm were investigated by B-mode ultrasound (B-US) and CEUS. The homogeneity of enhancement (homogeneous and inhomogeneous) was examined retrospectively using CEUS. An inhomogeneous enhancement was defined as a perfused lesion with coexisting non-perfused areas (NPA).

RESULTS

On B-US, all 11 patients showed an interstitial syndrome (B-lines) with PPLs between 0.5 and 6 cm. On CEUS, all cases showed peripheral NPA during the complete CEUS examination. One patient underwent a partial lung resection with subsequent histopathological examination. The histological examination showed vasculitis, microthrombus in the alveolar capillary, and small obliterated vessels.

CONCLUSION

In our case series, PPLs in patients with RT-PCR-confirmed COVID-19 infection presented a CEUS pattern with NPA during the complete CEUS examination. Our findings suggest a peripheral pulmonary perfusion disturbance in patients with COVID-19 infection. In 1 case, the histopathological correlation with the perfusion disturbance in the PPL was proven.

Cancer as a Model System for Testing Metabolic Scaling Theory

Biological allometries, such as the scaling of metabolism to mass, are hypothesized to result from natural selection to maximize how vascular networks fill space yet minimize internal transport distances and resistance to blood flow. Metabolic scaling theory argues two guiding principles—conservation of fluid flow and space-filling fractal distributions—describe a diversity of biological networks and predict how the geometry of these networks influences organismal metabolism. Yet, mostly absent from past efforts are studies that directly, and independently, measure metabolic rate from respiration and vascular architecture for the same organ, organism, or tissue. Lack of these measures may lead to inconsistent results and conclusions about metabolism, growth, and allometric scaling. We present simultaneous and consistent measurements of metabolic scaling exponents from clinical images of lung cancer, serving as a first-of-its-kind test of metabolic scaling theory, and identifying potential quantitative imaging biomarkers indicative of tumor growth. We analyze data for 535 clinical PET-CT scans of patients with non-small cell lung carcinoma to establish the presence of metabolic scaling between tumor metabolism and tumor volume. Furthermore, we use computer vision and mathematical modeling to examine predictions of metabolic scaling based on the branching geometry of the tumor-supplying blood vessel networks in a subset of 56 patients diagnosed with stage II-IV lung cancer. Examination of the scaling of maximum standard uptake value with metabolic tumor volume, and metabolic tumor volume with gross tumor volume, yield metabolic scaling exponents of 0.64 (0.20) and 0.70 (0.17), respectively. We compare these to the value of 0.85 (0.06) derived from the geometric scaling of the tumor-supplying vasculature. These results: (1) inform energetic models of growth and development for tumor forecasting; (2) identify imaging biomarkers in vascular geometry related to blood volume and flow; and (3) highlight unique opportunities to develop and test the metabolic scaling theory of ecology in tumors transitioning from avascular to vascular geometries.

US Contrast Agent Arrival Time Difference Ratio for Benign versus Malignant Subpleural Pulmonary Lesions

Background US has proven valuable in the diagnosis of subpleural pulmonary lesions (SPLs); however, existing US indicators have limitations. Purpose To propose and validate a revised contrast-enhanced (CE) US indicator for differential diagnosis of benign and malignant SPLs and to compare its performance with existing CE US diagnostic criteria. Materials and Methods This prospective study (Chinese clinical trial registry, ChiCTR1800019828) enrolled patients with SPLs between May 2019 and August 2020. They were divided into a developmental cohort (DC) and a validation cohort (VC). In the DC, the optimal indicator was selected from five CE US indicators. In the VC, the selected indicator was compared with existing CE US diagnostic criteria using the area under the receiver operating characteristic curve (AUC). Pathologic analysis, microbial evidence, and clinical follow-up were used as reference standards for all SPLs. Results A total of 902 participants (DC, 424 participants; VC, 478 participants) with SPLs (mean age, 56 years ± 17; 593 men) were evaluated. The arrival time (AT) difference ratio proved to be the optimal indicator to distinguish benign from malignant SPLs. In the overall (regardless of lesion size), large (vertical diameter >3 cm), and small (vertical diameter ≤3 cm) lesion groups, the cutoff values of the AT difference ratio were 43%, 42%, and 50% and the AUCs obtained from the VC were 0.91 (95% CI: 0.88, 0.93), 0.97 (95% CI: 0.94, 0.98), and 0.77 (95% CI: 0.71, 0.83) respectively, which were higher than those of lesion-lung AT difference greater than 2.5 seconds (0.81 [P < .001], 0.85 [P < .001], and 0.7 [P = .005], respectively), lesion AT greater than 7.5 seconds (0.65 [P < .001], 0.64 [P < .001], and 0.63 [P < .001], respectively), and lesion AT greater than 10 seconds (0.67 [P < .001], 0.68 [P < .001], and 0.64 [P < .001] respectively). Conclusion The US contrast agent arrival time difference ratio enables better differentiation of benign and malignant subpleural lesions when compared with existing diagnostic criteria. Online supplemental material is available for this article. Published under a CC BY 4.0 license.

Establishment of a large animal model for research on transbronchial arterial intervention for lung cancer

PURPOSE

We aimed to evaluate whether bronchial artery can supply a percutaneously inoculated canine transmissible venereal tumor (CTVT) in a lung tumor model.

METHODS

Fresh CTVT tissue blocks were percutaneously inoculated into unilateral or bilateral lungs of six immunosuppressed dogs at the mid zone of the middle or lower lobe. Tumor growth was monitored by computed tomography (CT). Ten weeks after inoculation, pulmonary arterial digital subtraction angiography (DSA), bronchial arterial DSA, transpulmonary arterial contrast-enhanced multislice CT, transbronchial arterial contrast-enhanced multislice CT (BA-MSCT), and transpulmonary arterial lipiodol multislice CT were performed.

RESULTS

Tumor growth was seen in all 10 inoculated sites, with a maximum diameter of 2.734±0.138 cm at 10th week. Bronchial arterial blood supply was evident in 9 nodules on DSA, and was equivocal in one which was later demonstrated on BA-MSCT. No obvious pulmonary arterial blood supply was observed in any of the nodules. Lipiodol deposition was displayed in two of the small distant metastases, which indicated that pulmonary artery was involved in the supply of the metastases.

CONCLUSION

Our results demonstrated bronchial arterial blood supply in this new lung cancer model. This model may be used in further research on transbronchial arterial intervention for lung cancer.

Cell-Secreted Vesicles: Novel Opportunities in Cancer Diagnosis, Monitoring and Treatment

Extracellular vesicles (EVs) are important mediators of intercellular communication playing a pivotal role in the regulation of physiological and pathological processes, including cancer. In particular, there is significant evidence suggesting that tumor-derived EVs exert an immunosuppressive activity during cancer progression, as well as stimulate tumor cell migration, angiogenesis, invasion and metastasis. The use of EVs as a liquid biopsy is currently a fast-growing area of research in medicine, with the potential to provide a step-change in the diagnosis and treatment of cancer, allowing the prediction of both therapy response and prognosis. EVs could be useful not only as biomarkers but also as drug delivery systems, and may represent a target for anticancer therapy. In this review, we attempted to summarize the current knowledge about the techniques used for the isolation of EVs and their roles in cancer biology, as liquid biopsy biomarkers and as therapeutic tools and targets.

Development and Prospective Validation of an Ultrasound Prediction Model for the Differential Diagnosis of Benign and Malignant Subpleural Pulmonary Lesions: A Large Ambispective Cohort Study

OBJECTIVE

To develop and prospective validate an ultrasound (US) prediction model to differentiate between benign and malignant subpleural pulmonary lesions (SPLs).

METHODS

This study was conducted retrospectively from July 2017 to December 2018 (development cohort [DC], n = 592) and prospectively from January to April 2019 (validation cohort [VC], n = 220). A total of 18 parameters of B-mode US and contrast-enhanced US (CEUS) were acquired. Based on the DC, a model was developed using binary logistic regression. Then its discrimination and calibration were verified internally in the DC and externally in the VC, and its diagnostic performance was compared with those of the existing US diagnostic criteria in the two cohorts. The reference criteria were from the comprehensive diagnosis of clinical-radiological-pathological made by two senior respiratory physicians.

RESULTS

The model was eventually constructed with 6 parameters: the angle between lesion border and thoracic wall, basic intensity, lung-lesion arrival time difference, ratio of arrival time difference, vascular sign, and non-enhancing region type. In both internal and external validation, the model provided excellent discrimination of benign and malignant SPLs (C-statistic: 0.974 and 0.980 respectively), which is higher than that of "lesion-lung AT difference ≥ 2.5 s" (C-statistic: 0.842 and 0.777 respectively, P <0.001) and "AT ≥ 10 s" (C-statistic: 0.688 and 0.641 respectively, P <0.001) and the calibration curves of the model showed good agreement between actual and predictive malignancy probabilities. As for the diagnosis performance, the sensitivity and specificity of the model [sensitivity: 94.82% (DC) and 92.86% (VC); specificity: 92.42% (DC) and 92.59% (VC)] were higher than those of "lesion-lung AT difference ≥ 2.5 s" [sensitivity: 88.11% (DC) and 80.36% (VC); specificity: 80.30% (DC) and 75.00% (VC)] and "AT ≥ 10 s" [sensitivity: 64.94% (DC) and 61.61% (VC); specificity: 72.73% (DC) and 66.67% (VC)].

CONCLUSION

The prediction model integrating multiple parameters of B-mode US and CEUS can accurately predict the malignancy probability, so as to effectively differentiate between benign and malignant SPLs, and has better diagnostic performance than the existing US diagnostic criteria.

CLINICAL TRIAL REGISTRATION

www.chictr.org.cn, identifier ChiCTR1800019828.

In vivo targeting of lentiviral vectors pseudotyped with the Tupaia paramyxovirus H glycoprotein bearing a cell-specific ligand

Despite their exceptional capacity for transgene delivery ex vivo, lentiviral (LV) vectors have been slow to demonstrate clinical utility in the context of in vivo applications. Unresolved safety concerns related to broad LV vector tropism have limited LV vectors to ex vivo applications. Here, we report on a novel LV vector-pseudotyping strategy involving envelope glycoproteins of Tupaia paramyxovirus (TPMV) engineered to specifically target human cell-surface receptors. LV vectors pseudotyped with the TPMV hemagglutinin (H) protein bearing the interleukin (IL)-13 ligand in concert with the TPMV fusion (F) protein allowed efficient transduction of cells expressing the human IL-13 receptor alpha 2 (IL-13Rα2). Immunodeficient mice bearing orthotopically implanted human IL-13Rα2 expressing NCI-H1299 non-small cell lung cancer cells were injected intravenously with a single dose of LV vector pseudotyped with the TPMV H-IL-13 glycoprotein. Vector biodistribution was monitored using bioluminescence imaging of firefly luciferase transgene expression, revealing specific transduction of tumor tissue. A quantitative droplet digital PCR (ddPCR) analysis of lung tissue samples revealed a >15-fold increase in the tumor transduction in mice treated with LV vectors displaying IL-13 relative to those without IL-13. Our results show that TPMV envelope glycoproteins can be equipped with ligands to develop targeted LV vectors for in vivo applications.

A pictorial review of the utility of CEUS in thoracic biopsies

Lung cancer is one of the commonest malignancies worldwide and necessitates both early and personalised treatment. A key requirement is histological sampling with immunohistochemistry obtained usually from percutaneous biopsy. Conventionally thoracic biopsies are performed using CT guidance, but more recently, there has been development of physician led ultrasound biopsy for pleural lesions. Contrast-enhanced ultrasound (CEUS) has been increasingly used in interventional procedures and is able to offer benefits for thoracic biopsies including improving lesional visualisation and characterisation, targeting viable tissue and avoiding critical vascular structures as well as evaluating for the presence of post-procedural complications. This educational review aims to benefits of the role of CEUS in thoracic biopsies.

Progress on pivotal role and application of exosome in lung cancer carcinogenesis, diagnosis, therapy and prognosis

Lung cancer is often diagnosed at an advanced stage and has a poor prognosis. Conventional treatments are not effective for metastatic lung cancer therapy. Although some of molecular targets have been identified with favorable response, those targets cannot be exploited due to the lack of suitable drug carriers. Lung cancer cell-derived exosomes (LCCDEs) receive recent interest in its role in carcinogenesis, diagnosis, therapy, and prognosis of lung cancer due to its biological functions and natural ability to carry donor cell biomolecules. LCCDEs can promote cell proliferation and metastasis, affect angiogenesis, modulate antitumor immune responses during lung cancer carcinogenesis, regulate drug resistance in lung cancer therapy, and be now considered an important component in liquid biopsy assessments for detecting lung cancer. Therapeutic deliverable exosomes are emerging as promising drug delivery agents specifically to tumor high precision medicine because of their natural intercellular communication role, excellent biocompatibility, low immunogenicity, low toxicity, long blood circulation ability, biodegradable characteristics, and their ability to cross various biological barriers. Several studies are currently underway to develop novel diagnostic and prognostic modalities using LCCDEs, and to develop methods of exploiting exosomes for use as efficient drug delivery vehicles. Current status of lung cancer and extensive applicability of LCCDEs are illustrated in this review. The promising data and technologies indicate that the approach on LCCDEs implies the potential application of LCCDEs to clinical management of lung cancer patients.

Time Difference of Arrival on Contrast-Enhanced Ultrasound in Distinguishing Benign Inflammation From Malignant Peripheral Pulmonary Lesions

Introduction

Worldwide, the incidence and mortality of lung cancer are at the highest levels, and the most lesions are located in the lung periphery. Despite extensive screening and diagnosis, the pathologic types of peripheral pulmonary lesions (PPLs) are difficult to diagnose by noninvasive examination. This study aimed to identify a novel index—time difference of arrival (TDOA)—to discriminate between benign inflammation and malignant PPLs.

Methods

Using contrast-enhanced ultrasound (CEUS), we retrospectively analyzed 96 patients with PPLs who had undergone biopsy to confirm the pathologic types. All data were collected from Dazhou Central Hospital between December 2012 and July 2019. The parameters of CEUS were analyzed by two assistant chief physicians of ultrasound diagnosis. Area under the receiver operating characteristic curve analysis, sensitivity, specificity, positive predictive value, and negative predictive value were calculated to assess the diagnostic ability of different indices.

Results

We found that the TDOA significantly distinguished benign inflammation from malignant lesions. The TDOA was markedly increased in patients with malignant lesions than benign inflammation lesions (P < 0.001). Compared with conventional time-intensity curve (TIC) indices, TDOA showed high diagnostic accuracy (area under the curve = 0.894). Moreover, conventional diagnostic indices did not affect the diagnostic performance of TDOA by adjusting the receiver operating characteristic curve.

Conclusion

TDOA is feasible for the diagnosis of benign inflammation and malignant PPLs.

Endothelial Progenitors in the Tumor Microenvironment

Tumor vascularization refers to the formation of new blood vessels within a tumor and is considered one of the hallmarks of cancer. Tumor vessels supply the tumor with oxygen and nutrients, required to sustain tumor growth and progression, and provide a gateway for tumor metastasis through the blood or lymphatic vasculature. Blood vessels display an angiocrine capacity of supporting the survival and proliferation of tumor cells through the production of growth factors and cytokines. Although tumor vasculature plays an essential role in sustaining tumor growth, it represents at the same time an essential way to deliver drugs and immune cells to the tumor. However, tumor vasculature exhibits many morphological and functional abnormalities, thus resulting in the formation of hypoxic areas within tumors, believed to represent a mechanism to maintain tumor cells in an invasive state.Tumors are vascularized through a variety of modalities, mainly represented by angiogenesis, where VEGF and other members of the VEGF family play a key role. This has represented the basis for the development of anti-VEGF blocking agents and their use in cancer therapy: however, these agents failed to induce significant therapeutic effects.Much less is known about the cellular origin of vessel network in tumors. Various cell types may contribute to tumor vasculature in different tumors or in the same tumor, such as mature endothelial cells, endothelial progenitor cells (EPCs), or the same tumor cells through a process of transdifferentiation. Early studies have suggested a role for bone marrow-derived EPCs; these cells do not are true EPCs but myeloid progenitors differentiating into monocytic cells, exerting a proangiogenic effect through a paracrine mechanism. More recent studies have shown the existence of tissue-resident endothelial vascular progenitors (EVPs) present at the level of vessel endothelium and their possible involvement as cells of origin of tumor vasculature.

An Integrated Gene Expression Landscape Profiling Approach to Identify Lung Tumor Endothelial Cell Heterogeneity and Angiogenic Candidates

Heterogeneity of lung tumor endothelial cell (TEC) phenotypes across patients, species (human/mouse), and models (in vivo/in vitro) remains poorly inventoried at the single-cell level. We single-cell RNA (scRNA)-sequenced 56,771 endothelial cells from human/mouse (peri)-tumoral lung and cultured human lung TECs, and detected 17 known and 16 previously unrecognized phenotypes, including TECs putatively regulating immune surveillance. We resolved the canonical tip TECs into a known migratory tip and a putative basement-membrane remodeling breach phenotype. Tip TEC signatures correlated with patient survival, and tip/breach TECs were most sensitive to vascular endothelial growth factor blockade. Only tip TECs were congruent across species/models and shared conserved markers. Integrated analysis of the scRNA-sequenced data with orthogonal multi-omics and meta-analysis data across different human tumors, validated by functional analysis, identified collagen modification as a candidate angiogenic pathway.

Pre-treatment serum bicarbonate predicts for primary tumor control after stereotactic body radiation therapy in patients with localized non-small cell lung cancer

BACKGROUND

Tumor aggressiveness and hypoxia are linked to acidosis in the tumor microenvironment (TME). We hypothesized that low pre-treatment serum bicarbonate, potentially correlating with an acidic and hypoxic TME, predicts for poor outcomes after stereotactic body radiation therapy (SBRT) for non-small cell lung cancer (NSCLC).

METHODS

We included patients with localized NSCLC treated to a biologically effective dose (BED) ≥ 100 Gy, with available pre-treatment bicarbonate values within 3 months of treatment. We used receiver operating characteristic analysis to determine the bicarbonate concentration optimally predicting for primary tumor recurrence, and evaluated its association with recurrence and survival. We validated our findings in an independent cohort of patients from three collaborating institutions.

RESULTS

A total of 110 patients and 114 tumors were included in the training cohort, with median follow-up of 15.0 months. Bicarbonate < 26 mEq/L was associated with primary tumor recurrence on univariate (HR = 5.92; 95% CI 1.69-24.88; p = 0.005) and multivariate analysis (HR = 5.48; 95% CI 1.37-25.19; p = 0.020). The validation cohort consisted of 195 patients and 208 tumors with median follow-up of 27.5 months. In the validation cohort, bicarbonate < 26 mEq/L was again associated with primary tumor recurrence on univariate (HR = 3.38; 95% CI 1.27-9.37; p = 0.015) and multivariate analysis (HR = 3.33; 1.18-10.07; p = 0.023).

CONCLUSIONS

Pre-treatment bicarbonate predicts for primary tumor control in NSCLC treated with SBRT and may be useful for risk stratification. These findings should be confirmed prospectively.

Angiogenesis Inhibitors for the Treatment of Ovarian Cancer: An Updated Systematic Review and Meta-analysis of Randomized Controlled Trials

Supplemental digital content is available in the text.

Background

Angiogenesis inhibitors showed activity in ovarian cancer, but preliminary data could not accurately reflect the survival benefit. We thus did a systematic review and meta-analysis of randomized controlled trials to reassess the efficacy and safety of angiogenesis inhibitors combined with chemotherapy for ovarian cancer.

Methods

We searched PubMed, EMBASE, Cochrane, and ClinicalTrials.gov for randomized controlled trials comparing angiogenesis inhibitors containing therapy with conventional chemotherapy alone or no further treatment. Our main outcomes were the progression-free survival (PFS), overall survival (OS), and common adverse events.

Results

Fifteen trials were included (N = 8721 participants). For newly diagnosed ovarian cancer, combination treatment with angiogenesis inhibitors and chemotherapy yielded a lower risk of disease progression (hazard ratio [HR], 0.83; 95% confidence interval (CI), 0.71–0.97) and no improved OS (HR, 0.95; 95% CI, 0.86–1.05). In the high-risk progression subgroup, the addition of bevacizumab significantly improved PFS (HR, 0.72; 95% CI, 0.65–0.81) and OS (HR, 0.84; 95%CI, 0.74–0.96). In recurrent patients, the combined HR was 0.58 (95% CI, 0.52–0.65) for PFS, and for OS, the combined HR was 0.86 (95% CI, 0.79–0.94). We found no significant improvement for either PFS (HR, 0.80; 95% CI, 0.63–1.01) or OS (HR, 1.06; 95% CI, 0.88–1.28) in the pure maintenance therapy.

In the overall population, angiogenesis inhibitors increased the incidence of gastrointestinal perforation (risk ratio [RR], 2.57; 95% CI, 1.66–3.97), hypertension (RR, 7.60; 95% CI, 2.79–20.70), arterial thromboembolism (RR, 2.27; 95% CI, 1.34–3.84), proteinuria (RR, 4.31; 95% CI, 2.15–8.64), and complication of wound healing (RR, 1.72, 95% CI, 1.12–2.63).

Conclusions

Combination treatment with angiogenesis inhibitors and chemotherapy significantly improved PFS and OS in both patients with high-risk of progression and recurrent ovarian cancer, with an increased incidence of common adverse events. Conversely, we detected no statistically significant survival benefit in the pure maintenance setting. The main limitation of the review is clinical heterogeneity across the studies.

The roles of tumor-derived exosomes in non-small cell lung cancer and their clinical implications

Non-small cell lung cancer (NSCLC) accounts for approximately 85% of lung cancer cases, and it is one of the leading causes of cancer death in both men and women worldwide due to diagnosis in the advanced stage, rapid metastasis, and recurrence. At present, precision molecular targeted therapeutics directed toward NSCLC driven genes has made great progress and significantly improved the overall survival of patients with NSCLC, but can easily lead to acquired drug resistance. New methods are needed to develop real-time monitoring of drug efficacy and drug resistance, such as new molecular markers for more effective early detection and prediction of prognosis. Exosomes are nano-sized extracellular vesicles, containing proteins, nucleic acids and lipids, which are secreted by various cells, and they play an important role in the development of lung cancer by controlling a wide range of pathways. Tumor-derived exosomes are of great significance for guiding the targeted therapy of NSCLC and exosomes themselves can be a target for treatment. In this review, we describe the potential roles of tumor-derived exosomes and their clinical significance in NSCLC.

CT Perfusion in Patients with Lung Cancer: Squamous Cell Carcinoma and Adenocarcinoma Show a Different Blood Flow

Objectives

To characterize tumour baseline blood flow (BF) in two lung cancer subtypes, adenocarcinoma (AC) and squamous cell carcinoma (SCC), also investigating those “borderline” cases whose perfusion value is closer to the group mean of the other histotype.

Materials and Methods

26 patients (age range 36-81 years) with primary Non-Small Cell Lung Cancer (NSCLC), subdivided into 19 AC and 7 SCC, were enrolled in this study and underwent a CT perfusion, at diagnosis. BF values were computed according to the maximum-slope method and unreliable values (e.g., arising from artefacts or vessels) were automatically removed. The one-tail Welch's t-test (p-value <0.05) was employed for statistical assessment.

Results

At diagnosis, mean BF values (in [mL/min/100g]) of AC group [(83.5 ± 29.4)] are significantly greater than those of SCC subtype [(57.0 ± 27.2)] (p-value = 0.02). However, two central SCCs undergoing artefacts from vena cava and pulmonary artery have an artificially increased mean BF.

Conclusions

The different hemodynamic behaviour of AC and SCC should be considered as a biomarker supporting treatment planning to select the patients, mainly with AC, that would most benefit from antiangiogenic therapies. The significance of results was achieved by automatically detecting and excluding artefactual BF values.

Angiogenesis in the lung

Both systemic (tracheal and bronchial) and pulmonary circulations perfuse the lung. However, documentation of angiogenesis of either is complicated by the presence of the other. Well-documented angiogenesis of the systemic circulations have been identified in asthma, cystic fibrosis, chronic thromboembolism and primary carcinomas. Angiogenesis of the vasa vasorum, which are branches of bronchial arteries, is seen in the walls of large pulmonary vessels after a period of chronic hypoxia. Documentation of increased pulmonary capillaries has been shown in models of chronic hypoxia, after pneumonectomy and in some carcinomas. Although endothelial cell proliferation may occur as part of the repair process in several pulmonary diseases, it is separate from the unique establishment of new functional perfusing networks defined as angiogenesis. Identification of the mechanisms driving the expansion of new vascular beds in the adult needs further investigation. Yet the growth factors and molecular mechanisms of lung angiogenesis remain difficult to separate from underlying disease sequelae.