PD-L1 as a Biomarker for the Efficacy of Durvalumab in Stage III EGFR Mutant NSCLC.

BACKGROUND/AIM: Durvalumab consolidation is less effective in patients with epidermal growth factor receptor mutant (EGFR M+) NSCLC. Studies of durvalumab on EGFR M+ NSCLC as an expression of programmed death-ligand 1 (PD-L1) expression are limited. The purpose of this study was to determine the effect of durvalumab on PD-L1 expression in EGFR M+ patients. PATIENTS AND METHODS: This study included 249 unresectable stage III NSCLC patients treated with durvalumab. The primary outcome was progression-free survival (PFS). Cox multivariate analysis was performed based on EGFR and PD-L1 statuses: EGFR M-, PD-L1 ≥50% (cohort A); EGFR M-, PD-L1 <50% (cohort B); EGFR M+, PD-L1 ≥50% (cohort C); and EGFR M+, PD-L1 <50% (cohort D). RESULTS: Overall, 31 of 249 (12.4%) and 218 of the 249 (87.6%) patients had EGFR M+ and EGFR M- NSCLC, respectively. Median PFSs and OSs did not differ (PFS: 16.6 vs. 18.7 months, p=0.591; OS: 37.4 vs. 35.7 months, p=0.271). Median PFS of cohort A did not significantly differ from the median PFSs of cohorts B and C, but it was significantly longer than the median PFS of cohort D (23.7 vs. 15.2 months, p=0.045). Cox multivariate analysis revealed that cohort D exhibited a worse PFS (adjusted hazard ratio=2.27, 95% confidence interval=1.11-4.66, p=0.025) compared with cohort A. Median OSs were not different between the four cohorts. CONCLUSION: Durvalumab consolidation provided similar benefit in EGFR M+ patients with PD-L1 ≥50% compared with EGFR M- patients. A therapeutic role of durvalumab in patients with EGFR M+, high PD-L1 unresectable stage III NSCLC should be considered.

The TOX-RAGE axis mediates inflammatory activation and lung injury in severe pulmonary infectious diseases.

Thymocyte selection-associated high-mobility group box (TOX) is a transcription factor that is crucial for T cell exhaustion during chronic antigenic stimulation, but its role in inflammation is poorly understood. Here, we report that TOX extracellularly mediates drastic inflammation upon severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection by binding to the cell surface receptor for advanced glycation end-products (RAGE). In various diseases, including COVID-19, TOX release was highly detectable in association with disease severity, contributing to lung fibroproliferative acute respiratory distress syndrome (ARDS). Recombinant TOX-induced blood vessel rupture, similar to a clinical signature in patients experiencing a cytokine storm, further exacerbating respiratory function impairment. In contrast, disruption of TOX function by a neutralizing antibody and genetic removal of RAGE diminished TOX-mediated deleterious effects. Altogether, our results suggest an insight into TOX function as an inflammatory mediator and propose the TOX-RAGE axis as a potential target for treating severe patients with pulmonary infection and mitigating lung fibroproliferative ARDS.

Risk Factors Associated with Misuse of Soft Mist Inhaler in Patients with Chronic Obstructive Pulmonary Disease.

Purpose: The use of inhaled bronchodilators is the mainstay of treatment for patients with chronic obstructive pulmonary disease (COPD). Although the soft mist inhaler (SMI) was developed to overcome the disadvantages of pressurized metered dose and drug powder inhalers, misuse during handling has been frequently observed in many studies. However, few studies have focused on SMI misuse among patients with COPD. Thus, we aimed to assess and identify the risk factors associated with SMI misuse among patients with COPD. Patient and Methods: In this prospective, observational, cross-sectional study, we enrolled patients with COPD who were undergoing SMI treatment between January 2018 and March 2020. An advanced nurse practitioner assessed the participants' handling of the device by using a check list. Results: Among 159 participants, 136 (85.5%) reported inhaler misuse. Duration of COPD and COPD assessment test (CAT) scores were positively associated with inhaler misuse; adherence and education level were negatively associated with inhaler misuse. In the multivariable analysis, a low educational level (less than high school), high CAT score (≥ 10), and short duration of COPD (≤ 2 years) were identified as risk factors for SMI misuse. Conclusion: SMI misuse remains common among patients with COPD. Therefore, clinicians should pay close attention to their patients using SMIs, especially in the early period after the diagnosis of COPD.

A prospective, open-label, randomized clinical trial to evaluate the efficacy and safety of remimazolam in patients undergoing EBUS-TBNA: REST trial design.

BACKGROUND: Remimazolam is safe and effective for moderate sedation during flexible bronchoscopy, but its safety and efficacy during endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) remains undetermined. The REST trial (NCT06275594) will be a prospective randomized study of remimazolam in patients undergoing EBUS-TBNA with conscious sedation. The primary aim is to evaluate whether remimazolam is safe and effective for moderate sedation during EBUS-TBNA compared to real-world midazolam and on-label midazolam. METHODS: The REST trial will recruit 330 patients from four university hospitals with mediastinal lesions suspected of being lung cancer who are eligible for EBUS-TBNA under moderate sedation. The participants will be randomized into groups using remimazolam, real-world midazolam, and on-label midazolam (US prescribing information dosage) to perform EBUS-TBNA for procedural sedation. The primary endpoint will be procedural success using composite measures. DISCUSSION: The REST trial will prospectively evaluate the efficacy and safety of remimazolam during EBUS-TBNA under moderate sedation. It will provide information for optimizing sedation modalities and contribute to practical benefits in patients undergoing EBUS-TBNA. TRIAL REGISTRATION: ClinicalTrials.gov (NCT06275594). Prospectively registered on 15 February 2024.

Durvalumab Consolidation After Chemoradiotherapy in Elderly Patients With Unresectable Stage III NSCLC: A Real-World Multicenter Study.

BACKGROUND: The PACIFIC trial demonstrated survival benefit of durvalumab after concurrent chemoradiotherapy (CCRT) in unresectable stage III non-small-cell lung cancer. Data on the effectiveness and safety of durvalumab in elderly patients is lacking. METHODS: This retrospective study was conducted between September 2017 and September 2022. Progression-free survival (PFS), overall survival (OS), recurrence patterns, first subsequent treatment after recurrence, factors associated with survival outcomes, and adverse events (AEs) were compared. RESULTS: Of the 286 patients, 120 (42.0%) were ≥ 70 years and 166 (58.0%) were < 70 years. The median PFS (17.7 vs. 19.4 months; P = .43) and median OS (35.7 months vs. not reached; P = .13) were similar between 2 groups. Proportion of patients who completed durvalumab was lower in elderly patients (27.5% vs. 39.2%; P = .040). In elderly patients, ECOG PS 0 or 1 was associated with better PFS, and being male and having received a cisplatin-based regimen during CCRT were factors associated with better and worse OS, respectively. In patients aged < 70 years, a PD-L1 ≥ 50% was associated with improved PFS and OS. Elderly patients experienced more treatment-related AEs, grade 3/4 AEs, permanent discontinuation of durvalumab, and treatment-related deaths. Among the AEs leading to permanent discontinuation or death, pulmonary AE was significantly more common in elderly patients. CONCLUSION: Durvalumab demonstrated similar outcomes in elderly compared to younger patients. However, AEs were more common in elderly patients. Thus, judicious selection of patients and chemotherapy regimens, coupled with careful AE monitoring, are important factors for ensuring optimal durvalumab treatment.

Endobronchial Ultrasound Using Guide Sheath-Guided Transbronchial Lung Biopsy in Ground-Glass Opacity Pulmonary Lesions without Fluoroscopic Guidance.

Diagnosing ground-glass opacity (GGO) pulmonary lesions poses challenges. This study evaluates the utility of radial probe endobronchial ultrasound-guided transbronchial lung biopsy (RP-EBUS-TBLB) in diagnosing GGO pulmonary lesions. A total of 1651 RP-EBUS procedures were performed during the study period. This study analyzed 115 GGO lesions. The EBUS visualization yield was 80.1%. Of 115 lesions, 69 (60%) were successfully diagnosed. The average size of diagnosed lesions was significantly larger than that of undiagnosed lesions (21.9 ± 7.3 vs. 17.1 ± 6.6 mm, p < 0.001). Diagnostic yield varied by lesion size: 50.0% for lesions <20 mm, 65.1% for 20-30 mm lesions, and 85.7% for lesions >30 mm. The mixed blizzard sign on EBUS appeared in 60.6% of mixed GGO lesions, with no cases in pure GGO lesions. Multivariable analyses showed that lesion size (odds ratio [OR], 1.10; 95% confidence interval [CI], 1.00-1.16; p < 0.001) and mixed blizzard sign on EBUS (OR, 20.92; CI, 7.50-58.31; p < 0.001) were significantly associated with diagnostic success. Pneumothorax and hemoptysis occurred in 1.7% and 2.6% of patients, respectively. RP-EBUS-TBLB without fluoroscopic guidance is a viable diagnostic approach for GGO pulmonary lesions with acceptable complications.

Spirometric Interpretation and Clinical Relevance According to Different Reference Equations.

BACKGROUND: Global Lung Function Initiative (GLI)-2012 reference equation is currently suggested for interpretation of spirometry results and a new local reference equation has been developed in South Korea. However, lung function profiles according to the different reference equations and their clinical relevance have not been identified in chronic obstructive pulmonary disease (COPD) patients. METHODS: Our cross-sectional study evaluated Choi's, Korean National Health and National Examination Survey (KNHANES)-VI, and GLI-2012 reference equations. We estimated the percentages of predictive forced expiratory volume in one second (FEV1) and airflow limitation severity according to reference equations and analyzed their associations with patient reported outcomes (PROs): COPD assessment test (CAT) score, St. George's Respiratory Questionnaire for COPD patients (SGRQ-C) score, and six minute walk distance (6MWD). RESULTS: In the eligible 2,180 COPD patients, lower predicted values of FEV1 and forced vital capacity (FVC) were found in GLI-2012 compared to Choi's and KNHANES-VI equations. GLI-2012 equation resulted in a lower proportion of patients being classified as FEV1 < 80% or FVC < 80% compared to the other equations. However, the Z-scores of FEV1 and FVC were similar between the KNHANES-VI and GLI-2012 equations. Three reference equations exhibited significant associations between FEV1 (%) and patient-reported outcomes (CAT score, SGRQ-C score, and 6MWD). CONCLUSION: GLI-2012 reference equation may not accurately reflect FEV1 (%) in the Korean population, but the Z-score using GLI-2012 equation can be a viable option for assessing FEV1 and airflow limitation in COPD patients. Similar to the other two equations, the GLI-2012 equation demonstrated significant associations with PROs.

Clinical implications of wheezing in patients with chronic obstructive pulmonary disease.

Background: Studies on the prevalence of wheezing in both the asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) and non-ACO groups, as well as the clinical characteristics of wheezing patients in each group, are rare. We examined the prevalence of wheezing in ACO patients and non-ACO patients, respectively. In addition, we aimed to determine clinical characteristics of patients with wheezing compared to those without wheezing in the ACO and non-ACO groups. Methods: We analyzed the data from the Korean COPD Subgroup Study (KOCOSS), a multicenter prospective cohort. We classified patients into four groups according to whether they were ACO patients or had self-reported wheezing based on the patient's answer to the COPD-specific version of St. George's Respiratory Questionnaire (SGRQ-C): ACO with wheezing, ACO without wheezing, non-ACO with wheezing, and non-ACO without wheezing. Clinical characteristics and exacerbations during 1-year follow up were compared among four groups. Results: Wheezing was present in about 56% of patients in the ACO and non-ACO groups. In both groups, patients with wheezing exhibited more severe symptoms, worse lung function, and a higher risk of exacerbation than those without wheezing. There was no association between blood eosinophil count and wheezing in both the ACO and non-ACO groups. During 1-year follow-up, the ACO with wheezing group experienced exacerbations the most frequently, followed by the non-ACO with wheezing group. Moreover, wheezing was an independent predictor of the risk of exacerbation in patients with COPD, irrespective of both the ACO phenotype and the severity of airflow limitation. The exacerbation risk was higher in COPD patients who experienced wheezing more frequently. Conclusions: Wheezing, reflecting more prominent airflow limitation and predicting exacerbation development, may serve as a severe phenotype of COPD rather than being indicative of an ACO phenotype.

Content preserving image translation with texture co-occurrence and spatial self-similarity for texture debiasing and domain adaptation.

Models trained on datasets with texture bias usually perform poorly on out-of-distribution samples since biased representations are embedded into the model. Recently, various image translation and debiasing methods have attempted to disentangle texture biased representations for downstream tasks, but accurately discarding biased features without altering other relevant information is still challenging. In this paper, we propose a novel framework that leverages image translation to generate additional training images using the content of a source image and the texture of a target image with a different bias property to explicitly mitigate texture bias when training a model on a target task. Our model ensures texture similarity between the target and generated images via a texture co-occurrence loss while preserving content details from source images with a spatial self-similarity loss. Both the generated and original training images are combined to train improved classification or segmentation models robust to inconsistent texture bias. Evaluation on five classification- and two segmentation-datasets with known texture biases demonstrates the utility of our method, and reports significant improvements over recent state-of-the-art methods in all cases.

Brain FDG PET for visualizing the relation between impaired lung function and cognitive decline in lung cancer: a preliminary study.

OBJECTIVE: Impaired lung function is associated with an increased risk for cognitive decline. F-18 fluorodeoxyglucose (FDG) PET is a well-known neurodegenerative biomarker for dementia. We investigated the association between lung and brain function using FDG PET in patients with lung cancer. METHODS: A random sub-sample of 102 patients with lung cancer and without a self-reported history of neuropsychiatric disorders were recruited and underwent both lung function tests and FDG PET scans before treatment. Lung function was analyzed as the percentage predicted value (% pred) of forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1). FDG uptake was measured as standardized uptake values (SUVs) in the frontal, parietal, temporal, and occipital cortices and cognition-related regions. Regional SUV ratios (SUVRs) were calculated by dividing the SUV in each region by the whole-brain SUV and were then evaluated against lung function indices and clinical variables. RESULTS: After excluding five patients with brain metastases, 97 patients were included in the final analysis (mean age, 67.7 ± 10.3 years). Mean FVC and mean FEV1 were 80.0% ± 15.4% and 77.6% ± 17.8%, respectively. Both FVC and FEV1 were positively correlated with SUVRs in all brain regions after adjusting the data for clinical variables. The degree of decrease in SUVRs related to lung function was not significantly different between cognition-related regions and other regions. CONCLUSION: Impaired lung function was associated with decreased glucose metabolism in all regions of the brain, indicating that cognitive decline related to decreased glucose metabolism may be due to reduced perfusion.

Low diffusion capacity predicts poor prognosis in extensive stage small cell lung cancer: a single-center analysis of 10 years.

BACKGROUND: Poor pulmonary function and chronic obstructive pulmonary disease (COPD) are associated with poorer overall survival (OS) in non-small-cell lung cancer (NSCLC) patients. Few studies have investigated the association between pulmonary function and OS in small-cell lung cancer (SCLC) patients. We compared the clinical characteristics of extensive disease SCLC (ED-SCLC) with or without moderately impaired diffusion capacity for carbon monoxide (DLco) and investigated the factors associated with survival in ED-SCLC patients. METHODS: This retrospective single-center study was performed between January 2011 and December 2020. Of the 307 SCLC patients who received cancer therapy during the study, 142 with ED-SCLC were analyzed. The patients were divided into DLco < 60% group and DLco ≥ 60% groups. OS and predictors of poor OS were analyzed. RESULTS: The median OS of the 142 ED-SCLC patients was 9.3 months and the median age was 68 years. In total, 129 (90.8%) patients had a history of smoking, and 60 (42.3%) had COPD. Thirty-five (24.6%) patients were assigned to the DLco < 60% group. Multivariate analysis revealed that DLco < 60% (odds ratio [OR], 1.609; 95% confidence interval [CI], 1.062-2.437; P = 0.025), number of metastases (OR, 1.488; 95% CI, 1.262-1.756; P < 0.001), and < 4 cycles of first-line chemotherapy (OR, 3.793; 95% CI, 2.530-5.686; P < 0.001) were associated with poor OS. Forty (28.2%) patients received < 4 cycles of first-line chemotherapy; the most common reason for this was death (n = 22, 55%) from grade 4 febrile neutropenia (n = 15), infection (n = 5), or massive hemoptysis (n = 2). The DLco < 60% group had a shorter median OS than the DLco ≥ 60% group (10.6 ± 0.8 vs. 4.9 ± 0.9 months, P = 0.003). CONCLUSIONS: In this study, approximately one quarter of the ED-SCLC patients had DLco < 60%. Low DLco (but not forced expiratory volume in 1 s or forced vital capacity), a large number of metastases, and < 4 cycles of first-line chemotherapy were independent risk factors for poor survival outcomes in patients with ED-SCLC.

Endobronchial ultrasound-guided re-biopsy of non-small cell lung cancer with acquired resistance after EGFR tyrosine kinase inhibitor treatment.

BACKGROUND: Few studies assessed the use of endobronchial ultrasound (EBUS)-guided re-biopsy for detecting the T790M mutation after epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) failure. METHODS: A total of 2996 EBUS procedures were performed during the study period (January 2019-June 2022). In total, 44 consecutive patients who underwent EBUS-guided re-biopsy (56 procedures) for detecting the T790M mutation were analyzed. The success rates and T790M mutation frequencies were analyzed according to the re-biopsy site and EBUS method. Multivariate logistic regression analyses were used to identify factors affecting the likelihood of the T790M mutation. RESULTS: The success rates for the mutation analyses using EBUS with a guide-sheath (EBUS-GS), EBUS guided transbronchial needle aspiration (EBUS-TBNA), and EBUS-GS with EBUS-TBNA for re-biopsy were 80.6% (29/36), 93.3% (14/15), and 100% (5/5), respectively. Patients who underwent lymph node biopsy using EBUS-TBNA had an increased rates of the T790M mutation compared with those undergoing lung biopsy using EBUS-GS (EBUS-TBNA, 60.0%; EBUS-GS with EBUS-TBNA, 40.0%; EBUS-GS, 11.1%; p < 0.001). In multivariate analysis, the use of a first-generation EGFR-TKI (odds ratio [OR], 4.29; 95% confidence interval [CI], 1.05-17.58; p = 0.043) was associated with occurrence of the T790M mutation. Re-biopsy of the metastatic site tended to be associated with a higher T790M mutation rate. Mild hemoptysis occurred in 3.6% (2/56) of the patients. CONCLUSIONS: EBUS-guided re-biopsy can be used for detecting the T790M mutation in patients who failed EGFR-TKI therapy. The T790M mutation frequency differed according to the re-biopsy site. The use of a first-generation EGFR-TKI was an independent predictor of the T790M mutation.

Cleavage-Responsive Biofactory T Cells Suppress Infectious Diseases-Associated Hypercytokinemia.

Severe infectious diseases, such as coronavirus disease 2019 (COVID-19), can induce hypercytokinemia and multiple organ failure. In spite of the growing demand for peptide therapeutics against infectious diseases, current small molecule-based strategies still require frequent administration due to limited half-life and enzymatic digestion in blood. To overcome this challenge, a strategy to continuously express multi-level therapeutic peptide drugs on the surface of immune cells, is established. Here, chimeric T cells stably expressing therapeutic peptides are presented for treatment of severe infectious diseases. Using lentiviral system, T cells are engineered to express multi-level therapeutic peptides with matrix metallopeptidases- (MMP-) and tumor necrosis factor alpha converting enzyme- (TACE-) responsive cleavage sites on the surface. The enzymatic cleavage releases γ-carboxyglutamic acid of protein C (PC-Gla) domain and thrombin receptor agonist peptide (TRAP), which activate endothelial protein C receptor (EPCR) and protease-activated receptor-1 (PAR-1), respectively. These chimeric T cells prevent vascular damage in tissue-engineered blood vessel and suppress hypercytokinemia and lung tissue damages in vivo, demonstrating promise for use of engineered T cells against sepsis and other infectious-related diseases.

Nanodiamond as a Cytokine Sponge in Infectious Diseases.

Cytokine release syndrome (CRS) is a systemic inflammatory response resulting in overexpression of cytokines in serum and tissues, which leads to multiple-organ failure. Due to rapid aggravation of symptoms, timely intervention is paramount; however, current therapies are limited in their capacity to address CRS. Here, we find that the intravenous injection of highly purified detonation-synthesized nanodiamonds (DND) can act as a therapeutic agent for treating CRS by adsorbing inflammatory cytokines. Highly purified DNDs successfully inactivated various key cytokines in plasma from CRS patients with pneumonia, septic shock, and coronavirus disease 2019 pandemic (COVID-19). The intravenous injection of the DND samples in a mouse sepsis model by cecal ligation and puncture significantly improved survival rates and prevented tissue damage by reducing the circulating inflammatory cytokines. The results of this study suggest that the clinical application of highly purified DND can provide survival benefits for CRS patients by adsorbing inflammatory cytokines.

Humoral and Cellular Responses to COVID-19 Vaccines in SARS-CoV-2 Infection-Naïve and -Recovered Korean Individuals.

In the face of a global COVID-19 vaccine shortage, an efficient vaccination strategy is required. Therefore, the immunogenicity of single or double COVID-19 vaccination doses (ChAdOX1, BNT162b2, or mRNA-1273) of SARS-CoV-2-recovered individuals was compared to that of unvaccinated individuals with SARS-CoV-2 infection at least one year post-convalescence. Moreover, the immunogenicity of SARS-CoV-2-naïve individuals vaccinated with a complete schedule of Ad26.CoV2.S, ChAdOX1, BNT162b2, mRNA-1273, or ChAdOX1/BNT162b2 vaccines was evaluated. Anti-SARS-CoV-2 S1 IgG antibody (S1-IgG), pseudotyped virus-neutralizing antibody titer (pVNT50), and IFN-γ ELISpot counts were measured. Humoral immune responses were significantly higher in vaccinated than in unvaccinated recovered individuals, with a 43-fold increase in the mean pVNT50 values. However, there was no significant difference in the pVNT50 and IFN-γ ELISpot values between the single- and double-dose regimens. In SARS-CoV-2-naïve individuals, antibody responses varied according to the vaccine type: BNT162b2 and mRNA-1273 induced similar levels of S1-IgG to those observed in vaccinated, convalescent individuals; in contrast, pVNT50 was much lower in SARS-CoV-2-naïve vaccinees than in vaccinated recovered individuals. Therefore, a single dose of ChAdOX1, BNT162b2, or mRNA-1273 vaccines would be a good alternative for recovered individuals instead of a double-dose regimen.

Assessment of Inhaler Satisfaction and Determinants of High Satisfaction Among Korean COPD Patients.

BACKGROUND: The Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines for chronic obstructive pulmonary disease (COPD) recommend considering patient preference when choosing an inhaler device. However, few studies have assessed both inhaler satisfaction and factors associated with high inhaler satisfaction. Therefore, we assessed inhaler satisfaction and determinants of high satisfaction in Korean COPD patients. METHODS: COPD patients were prospectively enrolled from January 2018 to November 2019. The 308 inhalers used by the 261 participants in this study included dry powder inhalers (Turbuhaler, Breezhaler, Ellipta, Diskus, and Genuair), a soft mist inhaler (Respimat), and pressurized metered dose inhalers (pMDIs). Inhaler satisfaction was assessed by the Feeling of Satisfaction with Inhaler (FSI-10) questionnaire. High inhaler satisfaction was defined as an FSI-10 ≥ 43. RESULTS: Among 261 COPD patients, 163 (62.5%) were highly satisfied with their inhaler device. The rates of high inhaler satisfaction for Turbuhaler, Breezhaler, Ellipta, Diskus, Genuair, Respimat, and pMDI usage were 40.0%, 67.2%, 66.7%, 50.0%, 55.6%, 63.4%, and 45.0%, respectively (P = 0.215). In univariate analyses, higher body mass index, non-current smoker, GOLD grades I and II, a modified Medical Research Council (mMRC) score < 2, lower inhaler puff burden, once daily usage of inhaler, and good inhaler adherence were associated with high inhaler satisfaction. In multivariate analyses, an mMRC score < 2, and good inhaler adherence were independently associated with high inhaler satisfaction. CONCLUSION: High inhaler satisfaction was associated with dyspnea symptom and good inhaler adherence in COPD patients. Effective strategies are needed including appropriate inhaler device selection, consideration of patient preference, and repeated inhaler education to improve patient satisfaction of inhalers.

Radial Probe Endobronchial Ultrasound Using Guide Sheath-Guided Transbronchial Lung Biopsy in Peripheral Pulmonary Lesions without Fluoroscopy.

BACKGROUND: Radial probe endobronchial ultrasound-guided transbronchial lung biopsy (RP-EBUS-TBLB) has improved the diagnostic yield of bronchoscopic biopsy of peripheral pulmonary lesions (PPLs). The diagnostic yield and complications of RP-EBUS-TBLB for PPLs vary depending on the technique, such as using a guide sheath (GS) or fluoroscopy. In this study, we investigated the utility of RP-EBUS-TBLB using a GS without fluoroscopy for diagnosing PPLs. METHODS: We retrospectively reviewed data from 607 patients who underwent RP-EBUS of PPLs from January 2019 to July 2020. TBLB was performed using RP-EBUS with a GS without fluoroscopy. The diagnostic yield and complications were assessed. Multivariable logistic regression analyses were used to identify factors affecting the diagnostic yields. RESULTS: The overall diagnostic accuracy was 76.1% (462/607). In multivariable analyses, the size of the lesion (≥20 mm; odds ratio [OR], 2.06; 95% confidence interval [CI], 1.27-3.33; p=0.003), positive bronchus sign in chest computed tomography (OR, 2.30; 95% CI, 1.40-3.78; p=0.001), a solid lesion (OR, 2.40; 95% CI, 1.31-4.41; p=0.005), and an EBUS image with the probe within the lesion (OR, 6.98; 95% CI, 4.38-11.12; p<0.001) were associated with diagnostic success. Pneumothorax occurred in 2.0% (12/607) of cases and chest tube insertion was required in 0.5% (3/607) of patients. CONCLUSION: RP-EBUS-TBLB using a GS without fluoroscopy is a highly accurate diagnostic method in diagnosing PPLs that does not involve radiation exposure and has acceptable complication rates.

Utility of Radial Probe Endobronchial Ultrasound Guided Transbronchial Lung Biopsy in Bronchus Sign Negative Peripheral Pulmonary Lesions.

BACKGROUND: The presence of the bronchus sign on chest computed tomography is associated with an increased diagnostic yield of radial probe endobronchial ultrasound-guided transbronchial lung biopsy (RP-EBUS-TBLB). However, the utility of RP-EBUS-TBLB for bronchus sign negative peripheral pulmonary lesions (PPLs) remains unknown. We investigated the utility of RP-EBUS-TBLB in bronchus sign negative PPLs. METHODS: We retrospectively reviewed data from 109 patients who underwent RP-EBUS for bronchus sign negative PPLs from January 2019 to August 2020. TBLB was performed using RP-EBUS with a guide sheath and without fluoroscopy. The EBUS visualization and TBLB diagnostic yields were assessed. Multivariable logistic regression analyses were used to identify factors affecting the EBUS visualization and diagnostic yields. RESULTS: The EBUS visualization yield was 74.1% (68/109). Of the 109 lung lesions, 92 were definitively diagnosed. The overall diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 50.5% (55/109), 34.9% (29/83), 100% (26/26), 100% (29/29), and 32.5% (26/80), respectively. In multivariable analyses, the size of the lesion (≥ 20 mm; odds ratio [OR], 2.62; 95% confidence interval [CI], 1.16-5.93; P = 0.021) and the distance from the pleura (> 10 mm; OR, 2.37; 95% CI, 1.02-5.52; P = 0.045) were associated with EBUS visualization. Regarding diagnostic yield, having the probe within the lesion (OR, 28.50; 95% CI, 6.26-129.85; P < 0.001) and a solid lesion (OR, 14.58; 95% CI, 2.64-80.38; P = 0.002) were associated with diagnostic success. Pneumothorax and hemoptysis occurred in 3.7% (4/109) and 0.9% (1/109), respectively, of the patients. CONCLUSION: RP-EBUS-TBLB using a GS can be considered a diagnostic method in bronchus sign negative solid PPLs. Having the probe within the lesion and a solid lesion were important for diagnostic success. Complication rates were acceptable.

Dual attention multiple instance learning with unsupervised complementary loss for COVID-19 screening.

Chest computed tomography (CT) based analysis and diagnosis of the Coronavirus Disease 2019 (COVID-19) plays a key role in combating the outbreak of the pandemic that has rapidly spread worldwide. To date, the disease has infected more than 18 million people with over 690k deaths reported. Reverse transcription polymerase chain reaction (RT-PCR) is the current gold standard for clinical diagnosis but may produce false positives; thus, chest CT based diagnosis is considered more viable. However, accurate screening is challenging due to the difficulty in annotation of infected areas, curation of large datasets, and the slight discrepancies between COVID-19 and other viral pneumonia. In this study, we propose an attention-based end-to-end weakly supervised framework for the rapid diagnosis of COVID-19 and bacterial pneumonia based on multiple instance learning (MIL). We further incorporate unsupervised contrastive learning for improved accuracy with attention applied both in spatial and latent contexts, herein we propose Dual Attention Contrastive based MIL (DA-CMIL). DA-CMIL takes as input several patient CT slices (considered as bag of instances) and outputs a single label. Attention based pooling is applied to implicitly select key slices in the latent space, whereas spatial attention learns slice spatial context for interpretable diagnosis. A contrastive loss is applied at the instance level to encode similarity of features from the same patient against representative pooled patient features. Empirical results show that our algorithm achieves an overall accuracy of 98.6% and an AUC of 98.4%. Moreover, ablation studies show the benefit of contrastive learning with MIL.