Bronchial Lesions Research Articles

Modern problems of bronchial tuberculosis in the world and the Russian Federation: A review

In the Russian Federation there is a positive trend in reducing the incidence of tuberculosis. However, there is a tendency to increase the prevalence of tuberculosis in the bronchi. According to foreign authors, the prevalence of bronchial tuberculosis ranges from 10% to 40%. There are no official statistics on the incidence of bronchial tuberculosis in the Russian Federation. The main contingent of bronchial tuberculosis lesions are young non-smoking women. At the same time, the most common target is the left main bronchus. Currently, no additional methods have been developed in the scheme of specific treatment of patients with pulmonary tuberculosis complicated by bronchial tuberculosis. It is important to understand that the eradication of MBT after an effective course of chemotherapy does not prevent the formation of cicatricial bronchial stenosis. It is also important to note that bacterial excretion in patients with bronchial tuberculosis is much more common than in patients with a comparable process in the lungs, but without bronchial damage. Consequently, tuberculosis of the trachea and bronchi has not only clinical, but also great epidemiological significance.

Causes and Diagnostic Significance of Coughing in Dogs with Endocardiosis

Introduction. Endocardiosis is the most widespread acquired cardiac disease in small dog breeds, characterised by the valvular degeneration leading to mitral insufficiency. Progression of mitral regurgitation leads to cardiac remodeling, increased left ventricular filling pressures, pulmonary hypertension and, eventually, myocardial dysfunction. Decreased exercise tolerance, dyspnea, anorexia, and coughing are the most often reported signs in dogs with endocardiosis. Coughing is often reported as the primary clinical sign of congestive heart failure in dogs with endocardiosis. The concomitant respiratory tract disease and compression of the left mainstem bronchus by the giant left atrium have also been suggested as the potential causes of coughing in these patients. However, the absence of relief from cough in dogs with endocardiosis when treated with calcium sensitizers and the registered improvement in systolic cardiac function makes doubtful the cardiogenic nature of coughing in endocardiosis. In other words, the clinical and diagnostic significance of coughing in dogs with endocardiosis has not been sufficiently studied. The aim of the present research is to determine the frequency of cough incidence in dogs with endocardiosis and to establish the pathognomonic nature of this symptom in endocardiosis, its clinical significance.Materials and Methods. The medical records of 49 dogs that have attended to the veterinary clinics of the “Vita” network (Rostov region) for cardiological examination in the period from September 1, 2021 to July 31, 2024 were analysed. The research was carried out using the following equipment: premium ultrasound scanner with improved image quality on the ZST+ Mindray Vetus 9 platform, Maxivet 400 veterinary X-ray digital DR system, and Poli-Spectrum–8/V computerassisted electrocardiograph.Results. The research allowed us to find out the following: although the cardiomegaly and the increase in the size of the left ventricle in endocardiosis can aggravate and intensify the clinical manifestation of coughing in dogs with degenerative diseases of the upper respiratory tract, they are not the necessary condition for the occurrence of coughing. Coughing in dogs with endocardiosis should be considered as a clinical sign of the concomitant inflammatory or degenerative disease of the upper respiratory tract, which should be taken into account in therapy and in the attempt to improve the quality of life of these animals.Discussion and Conclusion. We have found that only 57% of the dogs with clinically evident endocardiosis suffer from coughing, whereas it does not have the uniform nature. In dogs with cardiogenic pulmonary edema, a cough is not loud, is usually acute and is associated with the flow of fluid into the medium and large-sized bronchi. The chronic loud, hoarse cough, intensifying in the morning, is typical for dogs with endocardiosis and chronic bronchitis: these animals at the same time have the non-specific inflammatory lesion of the bronchial tree and lesion of the mitral valves. Most severe coughing, with the characteristic loud sound, is observed in dogs suffering from the elements of the upper respiratory tract collapse and cardiomegaly due to endocardiosis.

Transcript-Level Biomarkers of Early Lung Carcinogenesis in Bronchial Lesions

Premalignant lesions within the bronchial epithelium signify the initial phases of squamous cell lung carcinoma, posing challenges for detection via conventional methods. Instead of focusing solely on gene expression, in this study, we explore transcriptomic alterations linked to lesion progression, with an emphasis on protein-coding transcripts. We reanalyzed a publicly available RNA-Seq dataset on airway epithelial cells from 82 smokers with and without premalignant lesions. Transcript and gene abundance were quantified using kallisto, while differential expression and transcript usage analysis was performed utilizing sleuth and RATs packages. Functional characterization involved overrepresentation analysis via clusterProfiler, weighted coexpression network analysis (WGCNA), and network analysis via Enrichr-KG. We detected 5906 differentially expressed transcripts and 4626 genes, exhibiting significant enrichment within pathways associated with oxidative phosphorylation and mitochondrial function. Remarkably, transcript-level WGCNA revealed a single module correlated with dysplasia status, notably enriched in cilium-related biological processes. Notable hub transcripts included RABL2B (ENST00000395590), DNAH1 (ENST00000420323), EFHC1 (ENST00000635996), and VWA3A (ENST00000563389) along with transcription factors such as FOXJ1 and ZNF474 as potential regulators. Our findings underscore the value of transcript-level analysis in uncovering novel insights into premalignant bronchial lesion biology, including identification of potential biomarkers associated with early lung carcinogenesis.

Automatic lesion detection for narrow-band imaging bronchoscopy.

Early detection of cancer is crucial for lung cancer patients, as it determines disease prognosis. Lung cancer typically starts as bronchial lesions along the airway walls. Recent research has indicated that narrow-band imaging (NBI) bronchoscopy enables more effective bronchial lesion detection than other bronchoscopic modalities. Unfortunately, NBI video can be hard to interpret because physicians currently are forced to perform a time-consuming subjective visual search to detect bronchial lesions in a long airway-exam video. As a result, NBI bronchoscopy is not regularly used in practice. To alleviate this problem, we propose an automatic two-stage real-time method for bronchial lesion detection in NBI video and perform a first-of-its-kind pilot study of the method using NBI airway exam video collected at our institution. Given a patient's NBI video, the first method stage entails a deep-learning-based object detection network coupled with a multiframe abnormality measure to locate candidate lesions on each video frame. The second method stage then draws upon a Siamese network and a Kalman filter to track candidate lesions over multiple frames to arrive at final lesion decisions. Tests drawing on 23 patient NBI airway exam videos indicate that the method can process an incoming video stream at a real-time frame rate, thereby making the method viable for real-time inspection during a live bronchoscopic airway exam. Furthermore, our studies showed a 93% sensitivity and 86% specificity for lesion detection; this compares favorably to a sensitivity and specificity of 80% and 84% achieved over a series of recent pooled clinical studies using the current time-consuming subjective clinical approach. The method shows potential for robust lesion detection in NBI video at a real-time frame rate. Therefore, it could help enable more common use of NBI bronchoscopy for bronchial lesion detection.

Graph Perceiver Network for Lung Tumor and Bronchial Premalignant Lesion Stratification from Histopathology

Bronchial premalignant lesions (PMLs) precede the development of invasive lung squamous carcinoma (LUSC), posing a significant challenge in distinguishing those likely to advance to LUSC from those that might regress without intervention. In this context, we present a novel computational approach, the Graph Perceiver Network (GRAPE-Net), leveraging hematoxylin and eosin (H&E) stained whole slide images (WSIs) to stratify endobronchial biopsies of PMLs across a spectrum from normal to tumor lung tissues. GRAPE-Net outperforms existing frameworks in classification accuracy predicting LUSC, lung adenocarcinoma (LUAD), and non-tumor (normal) lung tissue on The Cancer Genome Atlas (TCGA) and Clinical Proteomic Tumor Analysis Consortium (CPTAC) datasets containing lung resection tissues while efficiently generating pathologist-aligned, class-specific heatmaps. The network was further tested using endobronchial biopsies from two data cohorts, containing normal to carcinoma in situ histology, and it demonstrated a unique capability to differentiate carcinoma in situ lung squamous PMLs based on their progression status to invasive carcinoma. The network may have utility in stratifying PMLs for chemoprevention trials or more aggressive follow-up.

Abstract 6097: The role of B-cell receptor repertoire in lung squamous premalignant lesions

Abstract Objective: B cells and plasma cells (PCs) play a vital role in the pathogenesis of lung cancer and provide prognostic predictive value. However, the role of B cells in the bronchial premalignant lesions (PMLs), the precursor of lung squamous cell carcinoma, is poorly understood. Prior work has shown that progression of proliferative subtype, a PML molecular subtype enriched with bronchial dysplasia, to a higher histology grade is associated with downregulation of antigen processing and presentation. In this study, we seek to understand the role of B cells, PCs, and the B-cell receptor (BCR) repertoire in progression of the bronchial PML. Methods: We performed bulk targeted BCR sequencing on 69 endobronchial biopsies obtained from 29 subjects at high-risk for developing lung cancer. The Immcantation pipeline were applied to obtain the V(D)J germline segment assignment using the human reference from IMGT, clonal cluster assignment, and mutational load quantification for each BCR sequences by pooling all the BCR sequences from the same subjects. The clones with frequency less than 10-4 were filtered out. We then performed the repertoire analysis, such as clonality diversity, isotype switching frequency, and somatic hypermutation rate (SHM) rate at sample levels and investigated the association with transcriptional signature derived from bulk RNA-seq and the clinical progression of PMLs. Results: The B cell and PC transcriptional signatures and B cell chemoattractants gene expression are associated with progression in proliferative subtype PMLs. The number of BCR clones, the class switch from IgG3 to IgG1, and the mutational rates of total and CDR3 regions were positively correlated with the B cells and PCs transcriptional signatures. Among the 31 PMLs of proliferative subtype, regressive lesions showed higher proportions of IgG heavy chain usage, higher SHM rate in CDR3 and total BCR regions, and higher frequency of class switch from IgD/M to IgG and from IgG3 to IgG1. Biopsies within the same patient had a higher proportion of shared BCR clones when they were sampled at the same timepoint than when they were sampled from the same anatomic location at different timepoints. The preserved clones of BCRs at the same anatomic location over different times had higher clonality, more class switch from IgD/M to IgG or IgA and from IgG3 to IgG1, and increased SHM rates than the non-preserved clones. Conclusions: These results suggest B and plasma cells exert anti-tumor effects that prevent bronchial PMLs from progressing to higher grade lesions by switching to IgG1 BCRs and increasing SHM rates. Citation Format: Darren J. Chiu, Carter Merenstein, Marc Lenburg, Sarah Mazzilli, Jennifer Beane. The role of B-cell receptor repertoire in lung squamous premalignant lesions [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6097.

Utility of auto fluorescence-guided biopsy in suspected lung cancer patients with bronchial mucosal lesions

BackgroundBronchoscopy is currently the most common technique for lung cancer diagnosis. Patients suspected of malignancy often undergo bronchoscopic examination, and biopsy is routinely used in patients with visible bronchial lesions. However, it is difficult to differentially diagnose lung cancer in patients with bronchial mucosal lesions. Thus, this study was conducted to investigate the utility of fluorescence-guided biopsy in suspected lung cancer patients with bronchial mucosal lesions. MethodsWe conducted a retrospective study in a single screening center to assess the sensitivity and specificity of fluorescence-guided biopsy compared with white light bronchoscopy (WLB) in patients with bronchial mucosal lesions. ResultsA total of 301 patients with bronchial mucosal lesions were enrolled in this study. The sensitivity for patients with fluorescence-guided biopsy was 60.3 % (95 % confidence interval [CI]: 53.1 %–67.1 %), which was higher than that of patients with WLB alone (45.2 %, 95 % CI: 38.2–52.4 %) (P = 0.0026). Additionally, compared with the WLB group, the fluorescence -guided biopsy group was found to have a significantly higher specificity (100 %, 95 % CI: 95.5–100 % versus 69.6 %, 95 % CI: 59.6–78.1 %), positive predictive value (100 %, 95 % CI: 96.1–100 % versus 74.3 %, 95 % CI: 65.5–81.7 %) and negative predictive value (56.3 %, 95 % CI: 48.8–63.6 % versus 39.4 %, 95 % CI: 32.3–47.0 %). ConclusionFluorescence-guided biopsy can serve as an important adjunct to WLB for the differential diagnosis of lung cancer in patients with bronchial mucosal lesions.

Understanding the Landscape of Bronchoscopy in Lung Cancer: Insights From Lesion Location, Gender, and Diagnostic Efficacy.

Lung cancer constitutes a critical global health concern. According to the International Agency for Research on Cancer's (IARC) GLOBOCAN 2020 estimates, lung canceris the leading cause of death in cancer patients. In areas where tuberculosis is prevalent, misdiagnosis and mistreatment frequently result from overlap, creating significant difficulties that delay diagnosis and treatment. Amid this complication, bronchoscopic techniques emerge as critical diagnostic tools, though their efficacy varies between studies. Our retrospective study, conducted from July 2021 to December 2022at the Department of Respiratory Medicine, Ganesh Shankar Vidyarthi Memorial Medical College, Kanpur, examined 156 participants withmalignancies. Our focus encompassed diverse lesions within the bronchial landscape, revealing intriguing findings. Bronchoscopic examinations unravelled prevalent abnormalities: 52 (33.3%) manifested as intraluminal growth, 48 (31.6%) as mucosal irregularities, and a less frequent (16, 10.3%) as an intraluminal bulge. Transbronchial needle aspiration stood out with a 10/11 (91%) positivity rate, biopsy came in second at 38/46 (83%), and bronchoalveolar lavage showed a 44/152 (29%) positivity rate.It was interesting to see how the lesions were spread out among the different types of histology. For example, squamous cell carcinoma showed 17/37 (46%) intraluminal growth, while adenocarcinoma showed 22/60 (36.7%) intraluminal growth and 4/60 (6.7%) intraluminal bulge. Moreover, a significant absence of abnormalities was observed in various lesions, underlining the intricacies of characterising bronchial lesions. Our study shows that direct tissue sampling is better and that new bronchoscopic technologies are important for diagnosing lesions that were hard to get to in the past. However, limitations in patient selection biases and the single-centre focus caution against generalised interpretations. Our research illuminates the pivotal role of bronchoscopic methods in diagnosing lung lesions, emphasising the necessity for continued advancements to enhance diagnostic accuracy and treatment efficacy in lung cancer subtypes.

Radiological Features of Changes in the Lungs Caused by Fast- or Slow-Growing Nontuberculous Mycobacteria

Objective: to compare radiological features of pulmonary nontuberculous mycobacterioses (NTM) caused by fast- or slow-growing mycobacteria.Material and methods. Radiological features of the disease were studied in 110 patients with newly diagnosed NTM. The patients were divided into two groups: 70 (63.6%) patients with slow-growing NTM and 40 (36.3%) with fast-growing NTM. The diagnosis was based on patient’s complaints, specified case history, radiological studies, clinical laboratory studies, sputum smear studies, bronchoalveolar lavage studies, different types of bronchial biopsies, and video-assisted thoracoscopic surgery resection samples. According to the results of high-resolution computed tomography (HRCT), a comparative analysis of the degree of involvement in the pathological process of such anatomical formations as parenchyma and stroma, vessels, bronchi, pleura and intrathoracic lymph nodes was carried out.Results. The analysis of HRCT studies showed that fast-growing NTM is not characterized by gross deformation of bronchopulmonary structures. There is a more pronounced infiltrative phase with the involvement of vessels, pleura and bronchial lesions of smaller generations, the formation of broncho-bronchiolectasias and symptoms of bronchiolitis, faster clinical and radiological involution under dynamic observation. Slow-growing NTM is characterized by a more severe deformation of bronchopulmonary structures with the formation of different-sized bronchiectasis, bronchogenic cavities, a more torpid course of the inflammatory process.Conclusion. Despite the similarities of clinical and radiological patterns of NTM, we established some distinguished features for slow-growing and fast-growing types.

Diagnostic Role of Bronchoscopic Brush Biopsy Guided by Thin-Section Computed Tomography in Peripheral Pulmonary Lesions

Objective: The diagnosis of peripheral pulmonary lesions (PPLs) is important as they may be malignant. It is difficult to diagnose PPLs in the absence of a diagnostic guiding tool. Computed tomography (CT) thin-section multiplanar reconstruction (MPR) images have been used as an alternative guide for bronchoscopic diagnosis of PPL. In this study, we aimed to investigate the diagnostic efficacy of MPR image guidance for PPL. Methods: Patients with PPL who underwent bronchoscopic brush biopsy guided by thoracic CT thin-section MPR images at our center were retrospectively reviewed. The distance of the lesion to the distal bronchus, the presence of the CT-Bronchus sign, the location of the PPL, and the size of the PPL were recorded from the hospital image record archive. The diagnosis rate was obtained from the procedure records. Results: The study included 92 cases. The mean PPL size was 40 ± 21 mm and the mean distal bronchial lesion distance was 27 ± 19 mm. A total of 49 (53.3%) patients had a positive CT-Bronchus sign. The diagnostic yield of the method was 48.9%. The diagnosis rate was significantly higher in patients with positive CT-Bronchus sign (67.3%) compared to those without (26.7%) (P = 0.001). Factors affecting the diagnosis in the logistic regression analysis were distal bronchial lesion distance, presence of CT-Bronchus sign,and localization of the lesion. Conclusion: CT thin-section MPR images can be used for bronchoscopy guidance in cases with PPL larger than 20 mm and positive CT-Bronchus sign in centers where an interventional radiology unit and other guidance tools are not available.

Prevalence, molecular markers, and outcome of bronchial squamous carcinoma in situ in high-risksubjects.

Bronchial squamous carcinoma in situ (CIS) is a preinvasive lesion that is thought to precede invasive carcinoma. We conducted prospective autofluorescence and white light bronchoscopy trials between 1992 and 2016 to assess the prevalence, molecular markers, and outcome of individuals with CIS and other preneoplastic bronchial lesions. Biopsies were evaluated at multiple levels and selected biopsies were tested for aneuploidy and DNA sequenced for TP53 mutation. Thirty-one individuals with CIS were identified. Twenty-two cases of CIS occurred in association with concurrent invasive carcinomas. Seven of the invasive tumors were radiographically occult. In two cases, CIS spread from the focus of invasive carcinoma into contralateral lung lobes, forming secondary invasive tumors. In nine cases, CIS occurred as isolated lesions and one progressed to invasive squamous carcinoma at the same site 40 months after discovery. In a second case, CIS was a precursor of carcinoma at a separate site in a different lobe. In seven cases CIS regressed to a lower grade or disappeared. High level chromosomal aneusomy was often associated with TP53 mutation and with invasive carcinoma. CIS most often occurs in association with invasive squamous carcinoma and may extend along the airways into distant lobes. In rare cases, CIS may be observed to directly transform into invasive carcinoma. CIS may be indicative of invasive tumor at a separate distant site. Isolated CIS may regress. Molecular changes parallel histological changes in CIS and may be used to map clonal expansion in the airways.

Infection with Influenzavirus A in a murine model induces epithelial bronchial lesions and distinct waves of innate immune-cell recruitment.

Inflammatory lesions after Influenza A viruses (IAV) are potential therapeutic target for which better understanding of post-infection immune mechanisms is required. Most studies to evaluate innate immune reactions induced by IAV are based on quantitative/functional methods and anatomical exploration is most often non-existent. We aimed to study pulmonary damage and macrophage recruitment using two-photon excitation microscopy (TPEM) after IAV infection. We infected C57BL/6 CD11c+YFP mice with A/Puerto Ricco/8/34 H1N1. We performed immune cell analysis, including flow cytometry, cytokine concentration assays, and TPEM observations after staining with anti-F4/80 antibody coupled to BV421. We adapted live lung slice (LLS) method for ex-vivo intravital microscopy to analyze cell motility. TPEM provided complementary data to flow cytometry and cytokine assays by allowing observation of bronchial epithelium lesions and spreading of local infection. Addition of F4/80-BV421 staining allowed us to precisely determine timing of recruitment and pulmonary migration of macrophages. Ex-vivo LLS preserved cellular viability, allowing us to observe acceleration of macrophage motility. After IAV infection, we were able to explore structural consequences and successive waves of innate immune cell recruitment. By combining microscopy, flow cytometry and chemokine measurements, we describe novel and precise scenario of innate immune response against IAV.

DNA methylome analysis reveals potential alterations contributing to the progression of bronchial hyperplasia.

Squamous cell lung cancer (SCLC) arises from bronchial changes: basal cell hyperplasia (BCH), squamous metaplasia (SM), and dysplasia. However, the premalignant process preceding SCLC is not inevitable; it can stop at any of the bronchial lesions. Previously, we hypothesized that combinations of premalignant lesions observed in the small bronchi of SCLC patients can reflect the different "scenarios" of the premalignant process: BCHi-the stoppage at the stage of hyperplasia and BCHSM-the progression of hyperplasia to metaplasia. In this study, using whole-genome bisulfite sequencing we analyzed the DNA methylome of two forms of BCH: isolated BCH (BCHi) and BCH co-occurred with SM (BCHSM) in the small bronchi of SCLC patients. It was shown that BCHi harbored differentially methylated regions (DMRs) affecting genes associated with regulating phosphatase activity. In BCHSM, DMRs were found in genes involved in PI3K-Akt and AMPK signaling pathways. DMRs were also found to affect specific miRNA genes: miR-34a and miR-3648 in BCHi and miR-924 and miR-100 in BCHSM. Thus, this study demonstrated the significant changes in DNA methylome between the isolated BCH and BCH combined with SM. The identified epigenetic alterations may underlie different "scenarios" of the premalignant process in the bronchial epithelium.

Abstract 5433: Representation learning for histological profiling of lung squamous premalignant lesions and tumors

Abstract Lung squamous cell carcinoma (LSCC) is preceded by the development of bronchial premalignant lesions (PMLs). PMLs progress through a series of histologic grades characterized by molecular and morphologic alterations. To enhance our understanding of PML progression to lung cancer, we are developing deep learning methods to quantitate PML histologic features and localize PML severity along the histologic disease spectrum. We leveraged whole slide images (WSIs) of lung tumors (lung adenocarcinoma, LUAD and LSCC) and non-involved adjacent (referred to as ‘normal’) tissue from the Clinical Proteomic Tumor Analysis Consortium (CPTAC), the National Lung Screening Trial (NLST) and the Cancer Genome Atlas (TCGA). The NLST WSIs were used for training a self-supervised contrastive learning (simCLR) model. A graph isomorphism network (GIN) trained on CPTAC WSIs was developed using the features from simCLR and perform WSI-level predictions on tissue subtype (LUAD, LSCC, normal). Model performance was assessed using area under the receiver operating curves (AUC). The model was used to learn WSI-level features of endobronchial biopsies of PMLs from two datasets (PCGA, n=365 samples spanning all histologic grades, and CIS, n=112, only high-grade samples). The features from the final layer of the GIN were used to compute principal components (PCs) and visualize the relationships between samples using t-SNE and UMAP. To interpret how the GIN processes WSI data, we performed gradient-based class activation mapping (Grad-CAMs) on the graphs. High model performance was observed on the CPTAC test dataset (Accuracy = 87%, AUC >= 0.89) but dropped slightly on the TCGA dataset (Accuracy = 72%, AUC >= 0.75). The GIN-CAMs identified WSI regions that were highly associated with the output label based on expert pathologist annotation on TCGA cases. Clustering revealed distinct groupings of normal, LUAD and LSCC subtypes (PC1 & PC2, p<0.01). Most WSIs from the PCGA data clustered with normal tissues (PC1 & PC2: p<0.01 for PCGA v LUAD, PCGA v LSCC). However, a portion of the CIS samples were closely grouped with LSCC tumor cases (74% of CIS WSIs were classified as LSCC tumors. PC1 & PC2: p<0.01 for CIS v LUAD; PC1: p<0.01 for CIS v LSCC). Additionally, the feature distribution of CIS samples that progressed towards LUSC tumors were significantly different than those that regressed (PC1 & PC3: p < 0.05 for Progressive v Regressive). The GIN recognizes and generates robust features that are distinctly and consistently observed in the different histologic groups across multiple cohorts. These features are also able to stratify progressive and regressive high-grade lesions. The stratification of PMLs is an important step in designing novel interception strategies to prevent the development of lung cancer, and our results suggest that pathology data may be efficacious to include in future biomarkers. Citation Format: Rushin Gindra, Yi Zheng, Regan Conrad, Emily Green, Sarah Mazzilli, Ehab Billatos, Mary Reid, Eric Burks, Vijaya Kolachalama, Jennifer E. Beane. Representation learning for histological profiling of lung squamous premalignant lesions and tumors. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5433.

Interrogating the precancerous evolution of pathway dysfunction in lung squamous cell carcinoma using XTABLE.

Lung squamous cell carcinoma (LUSC) is a type of lung cancer with a dismal prognosis that lacks adequate therapies and actionable targets. This disease is characterized by a sequence of low- and high-grade preinvasive stages with increasing probability of malignant progression. Increasing our knowledge about the biology of these premalignant lesions (PMLs) is necessary to design new methods of early detection and prevention, and to identify the molecular processes that are key for malignant progression. To facilitate this research, we have designed XTABLE (Exploring Transcriptomes of Bronchial Lesions), an open-source application that integrates the most extensive transcriptomic databases of PMLs published so far. With this tool, users can stratify samples using multiple parameters and interrogate PML biology in multiple manners, such as two- and multiple-group comparisons, interrogation of genes of interests, and transcriptional signatures. Using XTABLE, we have carried out a comparative study of the potential role of chromosomal instability scores as biomarkers of PML progression and mapped the onset of the most relevant LUSC pathways to the sequence of LUSC developmental stages. XTABLE will critically facilitate new research for the identification of early detection biomarkers and acquire a better understanding of the LUSC precancerous stages.

Focal 18 F-FDG uptake predicts progression of pre-invasive squamous bronchial lesions to invasive cancers.

Pre-invasive squamous lesions of the central airways can progress into invasive lung cancers. Identifying these high-risk patients could enable detection of invasive lung cancers at an early stage. In this study, we investigated the value of 18 F-fluorodeoxyglucose (18 F-FDG) positron emission tomography (PET) scans in predicting progression in patients with pre-invasive squamous endobronchial lesions. In this retrospective study, patients with pre-invasive endobronchial lesions, who underwent an 18 F-FDG PET scan at the VU University Medical Center Amsterdam, between January 2000 and December 2016, were included. Autofluorescence bronchoscopy (AFB) was used for tissue sampling and was repeated every 3 months. The minimum and median follow-up was 3 and 46.5months. Study endpoints were the occurrence of biopsy proven invasive carcinoma, time-to-progression and overall survival (OS). A total number of 40 of 225 patients met the inclusion criteria of which 17 (42.5%) patients had a positive baseline 18 F-FDG PET scan. A total of 13 of 17 (76.5%) developed invasive lung carcinoma during follow-up, with a median time to progression of 5.0months (range, 3.0-25.0). In 23 (57.5%) patients with a negative 18 F-FDG PET scan at baseline, 6 (26%) developed lung cancer, with a median time to progression of 34.0months (range, 14.0-42.0months, p < 0.002). With a median OS of 56.0months (range, 9.0-60.0 months) versus 49.0months (range, 6.0-60.0months) (p=0.876) for the18 F-FDG PET positive and negative groups, respectively. Patients with pre-invasive endobronchial squamous lesions and a positive baseline 18 F-FDG PET scan were at high-risk for developing lung carcinoma, highlighting that this patient group requires early radical treatment.

Issues in Medicine.

Rasmussen aneurysms are abnormalities of the pulmonary arterial system caused by tuberculosis (TB). They are associated with a highmortality rate when they cause life-threatening haemoptysis. High TB-prevalence regions have a large burden of TB-related haemoptysisbut often limited resources. This series of 25 patients who presented with life-threatening haemoptysis from current and/or previous TBwere found to have abnormal pulmonary arteries on computed tomography pulmonary angiogram (CTPA), which were judged to belikely contributors to their bleeding, either in isolation or with concomitant abnormal bronchial or systemic vasculature. These patientsunderwent transcatheter placement of Amplatzer vascular plugs in the feeder pulmonary artery. Bronchial and systemic lesions wereaddressed separately as needed. Immediate technical success was achieved in all patients, but four of them experienced intraoperativehaemoptysis related to dislodgement of the occluding platelet plug by the high-pressure automatic injector and wire. At 48 hours after theprocedure, 18 (72%) remained haemoptysis-free. Six of these experienced recurrence within 1 year of their procedure. Pulmonary arteryplacement of an Amplatzer vascular plug is a feasible option for treating bleeding Rasmussen aneurysms, but should be part of a combinedapproach to addressing suspected culprit vascular lesions in all intrathoracic vascular systems.

Abstract PR003: Multiplexed immune phenotyping and miRNA-ISH in bronchial premalignant lesions reveals a mechanism of immune suppression

Abstract Bronchial premalignant lesions (PMLs) are precursors of lung squamous cell carcinoma. Prior work has shown that among proliferative subtype PMLs, progression to or persistence of a high-grade histology is associated with downregulation of an immune-related gene module. Furthermore, microRNA-149 (miR-149) was identified as a candidate negative regulator of this expression program. In this study, we aim to investigate the spatial distribution of miR-149 and its association with the immune environment and PML progression/persistence in PMLs. We identified 19 paraffin embedded bronchial biopsies transcriptionally defined as belonging to the proliferative subtype obtained from 9 subjects. Three consecutive sections were stained with H&amp;E for histology annotation, chromogenic miRNA in situ hybridization (miRNA-ISH) for miR-149 abundance and localization, and with 30 antibodies targeted to epithelial and immune populations using imaging mass cytometry (IMC) to perform phenotyping. We trained a robust pixel classifier to detect foci of miR-149 signal in miRNA-ISH and quantified the density of miR-149 signal. For the IMC data, we used Mesmer for cell segmentation. PhenoGraph clustering based on quantification of each antibody in each cell was used for cell population identification. Ten recurrent cellular neighborhoods were identified by K-means clustering. miR-149 density was greater in the epithelium compared with stromal tissue. The miR-149 density in dysplastic epithelium normalized to miR-149 in normal epithelium is higher in the progressive/persistent PMLs than regressive PMLs. Additionally, in progressive/persistent PMLs, we find lower average epithelial staining for the miR-149 target NLRC5 associated with a cellular neighborhood that is enriched for goblet cells and PDL1+MUC5B+ secretory cells. Cell composition analysis showed that progressive/persistent PMLs have lower CD8 T cell infiltrate in both the stroma and epithelium. These results suggest that increased miR-149 expression in progressive/persistent PMLs contributes to an immune suppressive environment characterized by a shift in secretory cell populations and T cells within the bronchial epithelium. Interventions targeting miR-149 expression may be a potential interception strategy for high-grade PMLs. Citation Format: Darren J. Chiu, Roxana Pfefferkorn, Emily Green, Boting Ning, Myrtha Constant, Marc Lenburg, Eric Burks, Sarah Mazzilli, Jennifer Beane. Multiplexed immune phenotyping and miRNA-ISH in bronchial premalignant lesions reveals a mechanism of immune suppression. [abstract]. In: Proceedings of the AACR Special Conference: Precision Prevention, Early Detection, and Interception of Cancer; 2022 Nov 17-19; Austin, TX. Philadelphia (PA): AACR; Can Prev Res 2023;16(1 Suppl): Abstract nr PR003.

Abstract PR004: The role of NOTCH1 in bronchial pre-malignant lesions

Abstract Continuous carcinogen exposure through smoking creates a field of injury along the airway and resulting in mutations which promote remodeling of the bronchial epithelium. Over time lesions can form and exhibit increasing abnormalities progressing from goblet cell hyperplasia (GCH) which is the earliest detectable premalignant state through hyperplasia and squamous metaplasia to incremental stages of dysplasia, carcinoma in situ (CIS) and eventually to frank carcinoma. Unfortunately, more than half of all lung cancer patients are diagnosed with metastatic disease with a dismal 5-year survival rate of only 5.2%. However, when diagnosed at an early stage, the 5-year survival rate is more than 10 times as high. Our group has identified NOTCH1 as the most frequently mutated gene in progressive lung premalignant lesions (PMLs). However, these mutations are significantly less common in advanced lung squamous cell carcinoma (LUSC), indicating a role for NOTCH1 in the pre-tumorigenic environment rather than contributing to the actual tumor mass. Transcriptomic profiling of NOTCH1 mutated lesions identified up regulation of peri-goblet cells (PGC), a newly identified bronchial epithelial cell type that is associated with smoking, and a down regulation of immune components. Using highly multiplex Imaging Mass Cytometry (IMC) to analyze the epithelium of NOTCH1 mutated PMLs and its interplay with the immune system in situ. We identified a shift in epithelial composition with an increase in un- and de-differentiated cells. Interestingly, PGC appear to be an intermediate cell type on a previously undescribed path to goblet cell differentiation. In a parallel approach we are modeling NOTCH1 driven dysplasia in vitro to gain insight into the molecular mechanisms of lesion progression. Primary human bronchial epithelial cells (hBECs) grown at the air-liquid interface (ALI) into mature epithelia are exposed to cigarette smoke condensate (CSC) or IL-13 to model the early stages of bronchial airway dysplasia. Continuous exposure of these differentiating cultures to either stimulus increases the abundance of goblet cells and PGCs in a dose dependent manner with IL-13 additionally leading to the loss of baso-apical organization of the epithelium. After successfully modeling the first stage of bronchial epithelial dysplasia we are now advancing our model by co-culturing primary hBECs with NOTCH1 mutated cells and to disentangle the pathway of basal-PGC-goblet cell differentiation. Understanding driving forces in early lesion progression will further our ability to discern progressive lesions from those that regress naturally and facilitate interventions that force lesions into regression. Citation Format: Roxana Michaela Pfefferkorn, Darren Jianjhih Chiu, Divya Lakshmi Venkatraman, Jennifer Ellen Beane, Sarah Anne Mazzilli, Joshua David Campbell. The role of NOTCH1 in bronchial pre-malignant lesions. [abstract]. In: Proceedings of the AACR Special Conference: Precision Prevention, Early Detection, and Interception of Cancer; 2022 Nov 17-19; Austin, TX. Philadelphia (PA): AACR; Can Prev Res 2023;16(1 Suppl): Abstract nr PR004.

Dosimetric and Volumetric Analysis in Endobronchial Brachytherapy in Lung Carcinoma: A Cross-sectional Study

Introduction: High Dose Rate (HDR) brachytherapy plays an important role in the treatment of lung carcinoma. The treatment of lung carcinoma with Endobronchial Brachytherapy Treatment (EBBT) is delivered with three fractions and the effect of EBBT on the Target Volume (TV) after delivering the three fractions in the lung carcinoma needs to be assessed. The TV is covered with the prescribed dose and Organs At Risk (OARs) doses are evaluated. Aim: To assess the doses to OAR nearby the tumour and analyse the effect of the TV, tumour location, and site on the doses to OARs in EBBT in lung carcinoma. Materials and Methods: A cross-sectional study was conducted in the Department of Radiation Oncology, Cancer Research Institute, Himalayan Institute of Medical Sciences, Swami Rama Himalayan University Dehradun, Uttarakhand, India, from January 2018 to December 2020. Thirty patients with lung carcinoma were included in dosimetric and volumetric assessments. A flexible lumencare catheter was inserted into the bronchial lesion. Computed Tomography (CT) scan was acquired and exported to Treatment Planning System (TPS) through Digital Imaging and Communications in Medicine (DICOM) networking system. An optimised treatment plan was generated. The TV and OARs were delineated on the CT scan of the patient. A total of three EBBT sessions were given with a 7 Gy dose per fraction and prescribed the dose at 1.0 cm from the center of the catheter. Doses to OARs and the effects of TV on doses to OARs were evaluated with the help of “Dose Volume Histogram (DVH) tool” in the TPS. Thirty patients, with varying TV and site, were grouped as left lung and right lung tumour lesions and also grouped as TV &lt;22 cc and TV &gt;22 cc for the analysis purpose in this study. The data was entered in Microsoft Office Excel 2007 and analysed in Statistical Package for the Social Sciences (SPSS) version 22.0 statistical analysis software (IBM Corp., Armonk, N.Y., USA) tool. Results: The mean doses to OARs in 1st, 2nd and 3rd EBBT sessions were within their tolerance limit. The mean dose difference between left and right lung tumour site were analysed and found mainly the mean dose to oesophagus and maximum dose to oesophagus, contralateral lung, left coronary artery and descending aorta were significantly higher in left lung compared to right lung with p-value 0.015, 0.027, 0.001, 0.007 and 0.001, respectively. The maximum dose to the contralateral lung and spinal cord were significantly higher in middle-lower bronchial lesion with p-value 0.024 and 0.023, respectively. The mean dose difference between left and right lung tumour volume for TV &lt;22 cc and TV&gt;22 cc was analysed and found mainly for the group TV&gt;22 cc the mean dose to oesophagus and maximum dose to oesophagus, Heart, contralateral lung, left coronary artery and descending aorta were significantly higher in the left lung compared to right lung with p-value 0.002, 0.008, 0.027, 0.003, 0.006 and 0.001, respectively whereas in the TV&lt;22 cc group only the contralateral lung max dose was significantly higher in left lung compared to right lung with p-value 0.046. Conclusion: The OARs doses were increased significantly in left lung compared to right lung carcinoma. The TV was large in the middle-lower bronchial region, therefore, the doses were found higher, and TV in the lower bronchial region is less so the dose was less.