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Genomic profiling of bronchoalveolar lavage (BAL) samples may be useful for tumor profiling and diagnosis in the clinic. Here, we compared tumor-derived mutations detected in BAL samples from subjects with non–small cell lung cancer (NSCLC) to those detected in matched plasma samples. Cancer Personalized Profiling by Deep Sequencing (CAPP-Seq) was used to genotype DNA purified from BAL, plasma, and tumor samples from patients with NSCLC. The characteristics of cell-free DNA (cfDNA) isolated from BAL fluid were first characterized to optimize the technical approach. Somatic mutations identified in tumor were then compared with those identified in BAL and plasma, and the potential of BAL cfDNA analysis to distinguish lung cancer patients from risk-matched controls was explored. In total, 200 biofluid and tumor samples from 38 cases and 21 controls undergoing BAL for lung cancer evaluation were profiled. More tumor variants were identified in BAL cfDNA than plasma cfDNA in all stages (P < 0.001) and in stage I to II disease only. Four of 21 controls harbored low levels of cancer-associated driver mutations in BAL cfDNA [mean variant allele frequency (VAF) = 0.5%], suggesting the presence of somatic mutations in nonmalignant airway cells. Finally, using a Random Forest model with leave-one-out cross-validation, an exploratory BAL genomic classifier identified lung cancer with 69% sensitivity and 100% specificity in this cohort and detected more cancers than BAL cytology. Detecting tumor-derived mutations by targeted sequencing of BAL cfDNA is technically feasible and appears to be more sensitive than plasma profiling. Further studies are required to define optimal diagnostic applications and clinical utility. Significance: Hybrid-capture, targeted deep sequencing of lung cancer mutational burden in cell-free BAL fluid identifies more tumor-derived mutations with increased allele frequencies compared with plasma cell-free DNA. See related commentary by Rolfo et al., p. 2826

Supplementary Data from Genomic Profiling of Bronchoalveolar Lavage Fluid in Lung Cancer

Genomic profiling of bronchoalveolar lavage (BAL) samples may be useful for tumor profiling and diagnosis in the clinic. Here, we compared tumor-derived mutations detected in BAL samples from subjects with non–small cell lung cancer (NSCLC) to those detected in matched plasma samples. Cancer Personalized Profiling by Deep Sequencing (CAPP-Seq) was used to genotype DNA purified from BAL, plasma, and tumor samples from patients with NSCLC. The characteristics of cell-free DNA (cfDNA) isolated from BAL fluid were first characterized to optimize the technical approach. Somatic mutations identified in tumor were then compared with those identified in BAL and plasma, and the potential of BAL cfDNA analysis to distinguish lung cancer patients from risk-matched controls was explored. In total, 200 biofluid and tumor samples from 38 cases and 21 controls undergoing BAL for lung cancer evaluation were profiled. More tumor variants were identified in BAL cfDNA than plasma cfDNA in all stages (P < 0.001) and in stage I to II disease only. Four of 21 controls harbored low levels of cancer-associated driver mutations in BAL cfDNA [mean variant allele frequency (VAF) = 0.5%], suggesting the presence of somatic mutations in nonmalignant airway cells. Finally, using a Random Forest model with leave-one-out cross-validation, an exploratory BAL genomic classifier identified lung cancer with 69% sensitivity and 100% specificity in this cohort and detected more cancers than BAL cytology. Detecting tumor-derived mutations by targeted sequencing of BAL cfDNA is technically feasible and appears to be more sensitive than plasma profiling. Further studies are required to define optimal diagnostic applications and clinical utility.Significance:Hybrid-capture, targeted deep sequencing of lung cancer mutational burden in cell-free BAL fluid identifies more tumor-derived mutations with increased allele frequencies compared with plasma cell-free DNA.See related commentary by Rolfo et al., p. 2826

Supplementary Figure from Genomic Profiling of Bronchoalveolar Lavage Fluid in Lung Cancer

Background Two models, the Help with the Assessment of Adenopathy in Lung cancer (HAL) and Help with Oncologic Mediastinal Evaluation for Radiation (HOMER), were recently developed to estimate the probability of nodal disease in patients with non-small cell lung cancer (NSCLC) as determined by endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA). The objective of this study was to prospectively externally validate both models at multiple centers. Research Question Are the HAL and HOMER models valid across multiple centers? Study Design and Methods This multicenter prospective observational cohort study enrolled consecutive patients with PET-CT clinical-radiographic stages T1-3, N0-3, M0 NSCLC undergoing EBUS-TBNA staging. HOMER was used to predict the probability of N0 vs N1 vs N2 or N3 (N2|3) disease, and HAL was used to predict the probability of N2|3 (vs N0 or N1) disease. Model discrimination was assessed using the area under the receiver operating characteristics curve (ROC-AUC), and calibration was assessed using the Brier score, calibration plots, and the Hosmer-Lemeshow test. Results Thirteen centers enrolled 1,799 patients. HAL and HOMER demonstrated good discrimination: HAL ROC-AUC = 0.873 (95%CI, 0.856-0.891) and HOMER ROC-AUC = 0.837 (95%CI, 0.814-0.859) for predicting N1 disease or higher (N1|2|3) and 0.876 (95%CI, 0.855-0.897) for predicting N2|3 disease. Brier scores were 0.117 and 0.349, respectively. Calibration plots demonstrated good calibration for both models. For HAL, the difference between forecast and observed probability of N2|3 disease was +0.012; for HOMER, the difference for N1|2|3 was −0.018 and for N2|3 was +0.002. The Hosmer-Lemeshow test was significant for both models (P = .034 and .002), indicating a small but statistically significant calibration error. Interpretation HAL and HOMER demonstrated good discrimination and calibration in multiple centers. Although calibration error was present, the magnitude of the error is small, such that the models are informative.

Background: While the efficacy of Indwelling pleural catheters for palliation of malignant pleural effusions is supported by relatively robust evidence, there is less clarity surrounding the postinsertion management. Methods: The Trustworthy Consensus-Based Statement approach was utilized to develop unbiased, scientifically valid guidance for the management of patients with malignant effusions treated with indwelling pleural catheters. A comprehensive electronic database search of PubMed was performed based on a priori crafted PICO questions (Population/Intervention/Comparator/Outcomes paradigm). Manual searches of the literature were performed to identify additional relevant literature. Dual screenings at the title, abstract, and full-text levels were performed. Identified studies were then assessed for quality based on a combination of validated tools. Appropriateness for data pooling and formation of evidence-based recommendations was assessed using predetermined criteria. All panel members participated in development of the final recommendations utilizing the modified Delphi technique. Results: A total of 7 studies were identified for formal quality assessment, all of which were deemed to have a high risk of bias. There was insufficient evidence to allow for data pooling and formation of any evidence-based recommendations. Panel consensus resulted in 11 ungraded consensus-based recommendations. Conclusion: This manuscript was developed to provide clinicians with guidance on the management of patients with indwelling pleural catheters placed for palliation of malignant pleural effusions. Through a systematic and rigorous process, management suggestions were developed based on the best available evidence with augmentation by expert opinion when necessary. In addition, these guidelines highlight important gaps in knowledge which require further study.

BACKGROUND: Systemic arterial gas embolism (SAGE) is a rare yet serious and underrecognized complication of bronchoscopic procedures. A recent case of presumed SAGE after transbronchial needle aspiration prompted a systematic literature review of SAGE after biopsy procedures during flexible bronchoscopy. METHODS: We performed a systematic database search for case reports and case series pertaining to SAGE after bronchoscopic lung biopsy; reports or series involving only bronchoscopic laser therapy or argon plasma coagulation (APC) were excluded. Patient data were extracted directly from published reports. RESULTS: A total of 29 unique patient reports were assessed for patient demographics, specifics of the procedure, clinical manifestations, diagnostic findings, and clinical outcomes. Cases of SAGE occurred after multiple types of bronchoscopic biopsy and under both positive and negative pressure ventilation. The most common clinical findings were neurologic, followed by cardiac manifestations; temporal patterns included acute onset of cardiac or neurologic emergencies immediately after biopsy, or delayed awakening post-procedure. There was a high mortality rate among cases (28%), with residual neurologic deficits also common (24%). DISCUSSION: SAGE is an underrecognized but severe adverse effect of bronchoscopic lung biopsy, which often presents with acute coronary or cerebral ischemia or delayed awakening from sedation. It is important for all physicians who perform bronchoscopic biopsies to be aware of the clinical manifestations and therapeutic management of SAGE in order to mitigate morbidity and mortality among patients undergoing these procedures.

Background Endoprosthesis are being used in the everyday clinical practice either as a permanent solution or transient. They can be used in both benign and malignant situations. Case presentation We report a case in which a temporary Montgomery cannula is used in conjunction with therapeutic bronchoscopy to manage a patient with failed tracheostomy decannulation secondary to a distal complex tracheal stenosis. Conclusions This innovative use of the Montgomery cannula allowed for successful management of the patient's tracheal stenosis and subsequent tracheostomy tube decannulation.

Invasive pulmonary disease due to the mold Aspergillus fumigatus can be life-threatening in lung transplant recipients, but the risk factors remain poorly understood. To study this process, we used a tracheal allograft mouse model that recapitulates large airway changes observed in patients undergoing lung transplantation. We report that microhemorrhage-related iron content may be a major determinant of A. fumigatus invasion and, consequently, its virulence. Invasive growth was increased during progressive alloimmune-mediated graft rejection associated with high concentrations of ferric iron in the graft. The role of iron in A. fumigatus invasive growth was further confirmed by showing that this invasive phenotype was increased in tracheal transplants from donor mice lacking the hemochromatosis gene (Hfe-/- ). The invasive phenotype was also increased in mouse syngrafts treated with topical iron solution and in allograft recipients receiving deferoxamine, a chelator that increases iron bioavailability to the mold. The invasive growth of the iron-intolerant A. fumigatus double-knockout mutant (ΔsreA/ΔcccA) was lower than that of the wild-type mold. Alloimmune-mediated microvascular damage and iron overload did not appear to impair the host's immune response. In human lung transplant recipients, positive staining for iron in lung transplant tissue was more commonly seen in endobronchial biopsy sections from transplanted airways than in biopsies from the patients' own airways. Collectively, these data identify iron as a major determinant of A. fumigatus invasive growth and a potential target to treat or prevent A. fumigatus infections in lung transplant patients.

Background Propofol use for sedation during routine flexible bronchoscopy is expanding. However, there are concerns over propofol's reliability in targeting moderate sedation during more complex and lengthy procedures, such as endobronchial ultrasound (EBUS) bronchoscopy. Its delivery by continuous infusion, which provides a steady sedation effect, may be a practical model for achieving reliable outcomes in this setting. Methods We tested a continuous propofol infusion protocol targeting moderate sedation for EBUS bronchoscopy. A fixed loading rate of 125 mcg/kg/min and initial maintenance rate of 75 mcg/kg/min were used. Sedation assessments were performed every 2.5 minutes. The infusion was adjusted by a nurse under the direction of the bronchoscopist to maintain moderate sedation, normal vital signs, and patient comfort. Prospectively collected data from the first 31 patients using the protocol were analyzed. Results A mix of EBUS types was performed in a fellowship training environment. Median procedure duration was 51 minutes (interquartile range, 41 to 75 min). Ninety-four percent of total bronchoscopy time was spent in moderate sedation, whereas only 1.9% was occupied by agitation-related delays. Average propofol dose per case was 0.07 mg/kg/min (±0.020), and infusion adjustments were required once every 8 minutes. Sampling goals were met in all patients, and diagnostic and nodal staging accuracies were 90% and 91%, respectively. All tumor specimens sent for genetics were sufficient for analysis. There were no major procedure-related complications. Conclusion Bronchoscopist-directed continuous propofol infusion is effective and practical for reliably and safely targeting moderate sedation during EBUS bronchoscopy, without sacrificing the breadth and accuracy of the procedure.

Airway foreign body (FB) retrieval is synonymous with the birth of interventional pulmonology and bronchology. Once known to be a condition associated with significant morbidity and mortality, the advent of rigid bronchoscopy and other advanced bronchoscopic techniques has drastically improved outcomes related to FB aspiration. Patients that present with acute FB aspiration (hours/days after event) usually present with minimal signs of airway inflammation, while patients with retained FBs tend to have many associated complications such as severe airway inflammation, granulation tissue, bronchial stenosis, and/or post-obstructive pneumonia. The decision to use rigid and/or flexible bronchoscopy should be guided by the patient’s clinical presentation, FB features, and presence of inflammatory sequelae. The interventional pulmonologist has a multitude of techniques and instruments at his/her disposal to successfully manage the retrieval of FBs. Adequate knowledge and training combined with the ability to treat potential adverse events is required to ensure patient safety and to obtain the best outcome.

Estimating the probability of finding N2 or N3 (prN2/3) malignant nodal disease on endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in patients with non-small cell lung cancer (NSCLC) can facilitate the selection of subsequent management strategies.To develop a clinical prediction model for estimating the prN2/3.We used the AQuIRE (American College of Chest Physicians Quality Improvement Registry, Evaluation, and Education) registry to identify patients with NSCLC with clinical radiographic stage T1-3, N0-3, M0 disease that had EBUS-TBNA for staging. The dependent variable was the presence of N2 or N3 disease (vs. N0 or N1) as assessed by EBUS-TBNA. Univariate followed by multivariable logistic regression analysis was used to develop a parsimonious clinical prediction model to estimate prN2/3. External validation was performed using data from three other hospitals.The model derivation cohort (n = 633) had a 25% prevalence of malignant N2 or N3 disease. Younger age, central location, adenocarcinoma histology, and higher positron emission tomography-computed tomography N stage were associated with a higher prN2/3. Area under the receiver operating characteristic curve was 0.85 (95% confidence interval, 0.82-0.89), model fit was acceptable (Hosmer-Lemeshow, P = 0.62; Brier score, 0.125). We externally validated the model in 722 patients. Area under the receiver operating characteristic curve was 0.88 (95% confidence interval, 0.85-0.90). Calibration using the general calibration model method resulted in acceptable goodness of fit (Hosmer-Lemeshow test, P = 0.54; Brier score, 0.132).Our prediction rule can be used to estimate prN2/3 in patients with NSCLC. The model has the potential to facilitate clinical decision making in the staging of NSCLC.

Invasive pulmonary disease due to the mold Aspergillus fumigatus can be life-threatening in lung transplant recipients, but the risk factors remain poorly understood. To study this process, we used a tracheal allograft mouse model that recapitulates large airway changes observed in patients undergoing lung transplantation. We report that microhemorrhage-related iron content may be a major determinant of A. fumigatus invasion and, consequently, its virulence. Invasive growth was increased during progressive alloimmune-mediated graft rejection associated with high concentrations of ferric iron in the graft. The role of iron in A. fumigatus invasive growth was further confirmed by showing that this invasive phenotype was increased in tracheal transplants from donor mice lacking the hemochromatosis gene (Hfe−/−). The invasive phenotype was also increased in mouse syngrafts treated with topical iron solution and in allograft recipients receiving deferoxamine, a chelator that increases iron bioavailability to the mold. The invasive growth of the iron-intolerant A. fumigatus double-knockout mutant (ΔsreA/ΔcccA) was lower than that of the wild-type mold. Alloimmune-mediated microvascular damage and iron overload did not appear to impair the host’s immune response. In human lung transplant recipients, positive staining for iron in lung transplant tissue was more commonly seen in endobronchial biopsy sections from transplanted airways than in biopsies from the patients’ own airways. Collectively, these data identify iron as a major determinant of A. fumigatus invasive growth and a potential target to treat or prevent A. fumigatus infections in lung transplant patients.

Despite being a focus of intensive investigation, acute lung injury (ALI) remains a major cause of morbidity and mortality. However, the current consensus definition impedes identification of patients with ALI before they require mechanical ventilation. To establish a definition of early ALI (EALI), we carried out a prospective cohort study to identify clinical predictors of progression to ALI.Potential cases of EALI were identified by daily screening of chest radiographs (CXRs) for all adult emergency department and new medicine service admissions at Stanford University Hospital.Of 1,935 screened patients with abnormal CXRs, we enrolled 100 patients admitted with bilateral opacities present7 days and not due exclusively to left atrial hypertension. A total of 33 of these 100 patients progressed to ALI requiring mechanical ventilation during their hospitalization. Progression to ALI was associated with immunosuppression, the modified Rapid Emergency Medicine Score, airspace opacities beyond the bases, systemic inflammatory response syndrome, and the initial oxygen requirement (2 L/min). On multivariate analysis, only an initial oxygen requirement2 L/min predicted progression to ALI (odds ratio, 8.1; 95% confidence interval, 2.7 to 24.5). A clinical diagnosis of EALI, defined by hospital admission with bilateral opacities on CXR not exclusively due to left atrial hypertension and an initial oxygen requirement of2 L/min, was 73% sensitive and 79% specific for progression to ALI.A new clinical definition of EALI may have value in identifying patients with ALI early in their disease course.