First-in-human use of a new robotic electromagnetic navigation bronchoscopic platform with integrated Tool-in-Lesion Tomosynthesis (TiLT) technology for peripheral pulmonary lesions: The FRONTIER study.

BACKGROUND AND OBJECTIVE: As the presentation of pulmonary nodules increases, the importance of a safe and accurate method of sampling peripheral pulmonary nodules is highlighted. First-generation robotic bronchoscopy has successfully assisted navigation and improved peripheral reach during bronchoscopy. Integrating tool-in-lesion tomosynthesis (TiLT) may further improve yield. METHODS: We performed a first-in-human clinical trial of a new robotic electromagnetic navigation bronchoscopy system with integrated digital tomosynthesis technology (Galaxy System, Noah Medical). Patients with moderate-risk peripheral pulmonary nodules were enrolled in the study. Robotic bronchoscopy was performed using electromagnetic navigation with TiLT-assisted lesion guidance. Non-specific results were followed up until either a clear diagnosis was achieved or repeat radiology at 6 months demonstrated stability. RESULTS: Eighteen patients (19 nodules) were enrolled. The average lesion size was 20 mm, and the average distance from the pleura was 11.6 mm. The target was successfully reached in 100% of nodules, and the biopsy tool was visualized inside the target lesion in all cases. A confirmed specific diagnosis was achieved in 17 nodules, 13 of which were malignant. In one patient, radiological monitoring confirmed a true non-malignant result. This translates to a yield of 89.5% (strict) to 94.7% (intermediate). Complications included one pneumothorax requiring observation only and another requiring an overnight chest drain. There was one case of severe pneumonia following the procedure. CONCLUSION: In this first-in-human study, second-generation robotic bronchoscopy using electromagnetic navigation combined with integrated digital tomosynthesis was feasible with an acceptable safety profile and demonstrated a high diagnostic yield for small peripheral lung nodules.

Tracheobronchial stents: an expanding prospect.

The first dedicated tracheobronchial silicone stent was designed by the French pulmonologist Jean-Paul Dumon. The most common indications for stenting are to minimise extrinsic airway compression from mass effect, maintain airway patency due to intrinsic obstruction or treat significant nonmalignant airway narrowing or fistulae. Silicone stents require rigid bronchoscopy for insertion; however, they are more readily repositioned and removed compared with metallic stents. Metallic stents demonstrate luminal narrowing when loads are applied to their ends, therefore stents should either be reinforced at the ends or exceed the area of stenosis by a minimum of 5 mm. Nitinol, a nickel-titanium metal alloy, is currently the preferred material used for airway stents. Airway stenting provides effective palliation for patients with severe symptomatic obstruction. Drug-eluting and three-dimensional printing of airway stents present promising solutions to the challenges of the physical and anatomical constraints of the tracheobronchial tree. Biodegradable stents could also be a solution for the treatment of nonmalignant airway obstruction.

Cryobiopsy with radial-endobronchial ultrasound (Cryo-Radial) has comparable diagnostic yield with higher safety in comparison to computed tomography-guided transthoracic biopsy for peripheral pulmonary lesions: An exploratory randomised study.

BACKGROUND: Computed tomography-guided transthoracic biopsy (CT-TTB) is the 'gold standard' biopsy for lung nodules. Radial-endobronchial ultrasound (R-EBUS) bronchoscopy is another recommended biopsy but carries a lower diagnostic yield. Addition of cryobiopsy with R-EBUS (Cryo-Radial) has shown promising results. There are no studies comparing CT-TTB with Cryo-Radial biopsy. AIM: The co-primary aims were the diagnostic yeild and safety. The secondary aim: ability to test epidermal growth factor receptor (EGFR). METHODS: A randomised controlled, multicentre exploratory study was conducted at three tertiary hospitals. Patients with nodules >1 cm on CT of the chest were randomised to CT-TTB or Cryo-Radial. With Cryo-Radial, patients had 1-3 cryo-biopsies in addition to at least one R-EBUS biopsy through the 2.6 mm guide sheath. RESULTS: Forty-eight patients were randomised: 22 to CT-TTB and 26 to Cryo-Radial. Sixteen in the CT-TTB and 20 in the Cryo-Radial received the allocated biopsy. The diagnostic yield was CT-TTB 93.8% (15/16) versus Cryo-Radial 85% (17/20) P = 0.61 and the odds ratio was 0.37. For 5/13 (38%), a diagnosis was solely made on cryobiopsy. Eleven (78%) of 14 in CT-TTB versus 7/10 (70%) Cryo-Radial were suitable for EGFR testing P = 0.66, with odds ratio 0.63. Pneumothorax occurrence was 44% (7/16) in CT-TTB versus 4.2% (1/24) in Cryo-Radial. Two (12.5%) of 16 CT-TTB required chest drain insertion. CONCLUSION: Cryo-Radial is comparable in diagnostic yield and ability to perform EGFR testing with a significantly lower risk of pneumothorax, compared with CT-TTB. Cryo-Radial has the additional advantage of mediastinal staging during the same procedure with Linear-EBUS and is a promising first-line tool in the diagnostic method of lung cancer.

Reversal of collateral ventilation using endoscopic polymer foam in COPD patients undergoing endoscopic lung volume reduction with endobronchial valves: A controlled parallel group trial.

BACKGROUND AND OBJECTIVE: We have previously described reversal of collateral ventilation (CV) in a severe chronic obstructive pulmonary disease (COPD) patient with endoscopic polymer foam (EPF), prior to endoscopic lung volume reduction (ELVR) with valves. The aim of this study was to investigate the efficacy of this in a larger cohort and compare outcomes with a similar cohort with no CV. METHODS: Patients with severe COPD, with the left upper lobe (LUL) targeted for ELVR, were assessed for CV with high resolution computed tomography (HRCT). If fissure completeness was >95% they were enrolled as controls for valves alone (endobronchial valve control group [EBV-CTRL]). If fissure completeness was 80%-95%, defects were mapped to the corresponding segment, where EPF was instilled following confirmation of CV with CHARTIS. EBVs were inserted 1 month afterwards. RESULTS: Fourteen patients were enrolled into both arms. After 6 months, there were significant improvements in both groups in forced expiratory volume in 1 s (FEV1; +19.7% EPF vs. +27.7% EBV-CTRL, p < 0.05); residual volume (RV; -16.2% EPF vs. -20.1% EBV-CTRL, p = NS); SGRQ (-15.1 EPF vs. -16.6 EBV-CTRL p = NS) and 6 min walk (+25.8% EPF [77.2 m] vs. +28.4% [82.3 m] EBV-CTRL p = NS). Patients with fissural defects mapped to the lingula had better outcomes than those mapped to other segments (FEV1 +22.9% vs. +16.3% p < 0.05). There were no serious adverse reactions to EPF. CONCLUSION: EPF successfully reverses CV in severe COPD patients with a left oblique fissure that is 80%-95% complete. Following EBV, outcomes are similar to patients with complete fissures undergoing ELVR with EBV alone. EPF therapy to reverse CV potentially increases the number of COPD patients suitable for ELVR with minimal adverse reactions.

Development of a Bronchoscopy-Radiologic Skills and Task Assessment Tool (BRadSTAT): A Tool for Evaluating the Radiological Skills of Bronchoscopists with Different Experience.

BACKGROUND: Competency using radiologic images for bronchoscopic navigation is presumed during subspecialty training, but no assessments objectively measure combined knowledge of radiologic interpretation and ability to maneuver a bronchoscope into peripheral airways. OBJECTIVES: The objectives of this study were (i) to determine whether the Bronchoscopy-Radiology Skills and Tasks Assessment Tool (BRadSTAT) discriminates between bronchoscopists of various levels of experience and (ii) to improve construct validity using study findings. METHODS: BRadSTAT contains 10 questions that assess chest X-ray and CT scan interpretation using multiple images per question and 2 technical skill assessments. After administration to 33 bronchoscopists (5 Beginners, 9 Intermediates, 10 Experienced, and 9 Experts), discriminative power was strengthened using differential weighting on CT-related questions, producing the BRadSTAT-CT score. Cut points for both scores were determined via cross-validation. RESULTS: Mean BRadSTAT scores for Beginner, Intermediate, Experienced, and Expert were 74 (±13 SD), 78 (±14), 86 (±9), and 88 (±8), respectively. Statistically significant differences were noted between Expert and Beginner, Expert and Intermediate, and Experienced and Beginner (all p ≤ 0.05). Mean BRadSTAT-CT scores for Beginner, Intermediate, Experienced, and Expert were 63 (±14), 74 (±15), 82 (±13), and 90 (±9), respectively, all statistically significant (p ≤ 0.03). Cut points for BRadSTAT-CT had lower sensitivity but greater specificity and accuracy than for BRadSTAT. CONCLUSION: BRadSTAT represents the first validated assessment tool measuring knowledge and skills for bronchoscopic access to peripheral airways, which discriminates between bronchoscopists of various experience levels. Refining BRadSTAT produced the BRadSTAT-CT, which had higher discriminative power. Future studies should focus on their usefulness in competency-based bronchoscopy programs.

Cryobiopsy for Identification of Usual Interstitial Pneumonia and Other Interstitial Lung Disease Features. Further Lessons from COLDICE, a Prospective Multicenter Clinical Trial.

Rationale: Transbronchial lung cryobiopsy (TBLC) is an emerging technique for interstitial lung disease diagnosis. Good histopathologic agreement between TBLC and surgical lung biopsy (SLB) was demonstrated in the COLDICE (Cryobiopsy versus Open Lung Biopsy in the Diagnosis of Interstitial Lung Disease Alliance) study; however, diagnostic confidence was frequently lower for TBLC than SLB. Objectives: To characterize specific features of TBLC predictive of usual interstitial pneumonia (UIP) in corresponding SLB and to identify clinical indices predictive of biopsy concordance. Methods: The COLDICE study was a prospective, multicenter study investigating diagnostic agreement between TBLC and SLB. The participants underwent both procedures with blinded pathologist analysis of specimens, applying international guideline criteria. The TBLC features predictive of UIP in the paired SLB and predictive features of overall concordance were analyzed. Measurements and Main Results: A total of 65 patients (66.1 ± 9.3 yr; FVC, 84.7 ± 14.2%; DlCO, 63.4 ± 13.8%) participated in the COLDICE study. UIP was identified in 33/65 (50.8%) SLB, and 81.5% were concordant with corresponding TBLC (κ, 0.61; 95% confidence interval [CI], 0.38-0.77). The UIP guideline criteria of "predominantly subpleural or paraseptal fibrosis" was infrequently reported in TBLC (8/33, 24.2%), whereas "patchy fibrosis," "fibroblast foci," and the "absence of alternative diagnostic features" were frequently observed in TBLC. The combination of these three features strongly predicted UIP in paired SLB (odds ratio [OR], 23.4; 95% CI, 6.36-86.1; P < 0.0001). Increased numbers of TBLC samples predicted histopathologic concordance with SLB (OR, 1.8; 95% CI, 1.08-3.01; P = 0.03). The predictors of discordance included older age, family history, and radiologic asymmetry. Conclusions: Subpleural and/or paraseptal fibrosis were not essential for diagnosing UIP in TBLC, provided that other guideline criteria features were present. The diagnostic accuracy of TBLC was strengthened when increased numbers of samples were taken. Clinical trial registered with www.anzctr.org.au (ACTRN12615000718549).

Human papillomavirus (HPV) vaccination and oropharyngeal HPV in ethnically diverse, sexually active adolescents: community-based cross-sectional study.

OBJECTIVES: Oropharyngeal squamous cell carcinoma is the most common human papillomavirus (HPV)-associated cancer in the UK, but little is known about the prevalence of oropharyngeal HPV in sexually active teenagers. We investigated reported HPV vaccination coverage (in females) and prevalence of oropharyngeal HPV in sexually active students attending six technical colleges in London, UK. METHODS: In 2017, we obtained mouthwash samples and questionnaires from male and female students taking part in the 'Test n Treat' chlamydia screening trial. Samples were subjected to HPV genotyping. RESULTS: Of 232 participants approached, 202 (87%) provided a mouthwash sample and questionnaire. Participants' median age was 17 years and 47% were male. Most (73%) were from black and minority ethnic groups, 64% gave a history of oral sex, 52% reported having a new sexual partner in the past 6 months, 33% smoked cigarettes, 5.9% had concurrent genitourinary Chlamydia trachomatis infection and 1.5% Neisseria gonorrhoeae and 5.0% were gay or bisexual. Only 47% (50/107) of females reported being vaccinated against HPV 16/18, of whom 74% had received ≥2 injections. HPV genotyping showed three mouthwash samples (1.5%, 95% CI 0.3% to 4.3%) were positive for possible high-risk human papillomavirus (HR-HPV), one (0.5%, 0.0% to 2.7%) for low-risk HPV 6/11, but none (0.0%, 0.0% to 1.8%) for HR-HPV. Four samples (2.0%, 0.5% to 5.0%) were positive for HPV16 using a HPV16 type-specific quantitative PCR, but these were at a very low copy number and considered essentially negative. CONCLUSIONS: Despite the high prevalence of oral sex and genitourinary chlamydia and low prevalence of HPV vaccination, the prevalence of oropharyngeal HR-HPV in these adolescents was negligible.

Interventional bronchoscopy for chronic obstructive pulmonary disease: more than a pipe dream.

Endoscopic lung volume reduction (ELVR) is recognised in both national and international expert guidelines as one of the few additive treatments to benefit patients with advanced chronic obstructive pulmonary disease (COPD) who are otherwise receiving optimal medical and supportive care. Despite these recommendations and a growing evidence base, these procedures are not widely offered across Australia and New Zealand, and general practitioner and physician awareness of this therapy can be improved. ELVR aims to mitigate the impact of hyperinflation and gas trapping on dyspnoea and exercise intolerance in COPD. Effective ELVR is of proven benefit in improving symptoms, quality of life, lung function and survival. Several endoscopic techniques to achieve ELVR have been developed, with endobronchial valve placement to collapse a single lobe being the most widely studied and commonly practised. This review describes the physiological rationale underpinning lung volume reduction, highlights the challenges of patient selection, and provides an overview of the evidence for current and investigational endoscopic interventions for COPD.

Bronchial Rheoplasty for Treatment of Chronic Bronchitis. Twelve-Month Results from a Multicenter Clinical Trial.

Rationale: Chronic bronchitis (CB) is characterized by productive cough with excessive mucus production, resulting in quality-of-life impairment and increased exacerbation risk. Bronchial rheoplasty uses an endobronchial catheter to apply nonthermal pulsed electrical fields to the airways. Preclinical studies have demonstrated epithelial ablation followed by regeneration of normalized epithelium.Objectives: To evaluate the feasibility, safety, and initial outcomes of bronchial rheoplasty in patients with CB.Methods: Pooled analysis of two separate studies enrolling 30 patients undergoing bilateral bronchial rheoplasty was conducted. Follow-up through 6 months (primary outcome) and 12 months included assessment of adverse events, airway histology, and changes in symptoms using the Chronic Obstructive Pulmonary Disease (COPD) Assessment Test and St. George's Respiratory Questionnaire (SGRQ).Measurements and Main Results: Bronchial rheoplasty was performed in all 30 patients (63% male; mean [SD] age, 67 [7.4]; mean [SD] postbronchodilator FEV1, 65% [21%]; mean [SD] COPD Assessment Test score 25.6 [7.1]; mean [SD] SGRQ score, 59.6 [15.3]). There were no device-related and four procedure-related serious adverse events through 6 months, and there were none thereafter through 12 months. The most frequent nonserious, device- and/or procedure-related event through 6 months was mild hemoptysis in 47% (14 of 30) patients. Histologically, the mean goblet cell hyperplasia score was reduced by a statistically significant amount (P < 0.001). Significant changes from baseline to 6 months in COPD Assessment Test (mean, -7.9; median, -8.0; P = 0.0002) and SGRQ (mean, -14.6; median, -7.2; P = 0.0002) scores were observed, with similar observations through 12 months.Conclusions: This study provides the first clinical evidence of the feasibility, safety, and initial outcomes of bronchial rheoplasty in symptomatic patients with CB.Clinical trial registered with www.anzctr.org.au (ACTRN 12617000330347) and clinicaltrials.gov (NCT03107494).

Training in interventional pulmonology: What we have learned and a way forward.

IP encompasses a complex list of procedures requiring knowledge, technical skills and competence. Modern, learner-centric educational philosophies and an explosion of multidimensional educational tools including manikins, simulators, online resources, social media and formal programs can foster learning in IP, promoting professionalism and a culture of lifelong learning. This paper provides background and guidance to a structured, multidimensional and learner-centric strategy for medical procedural education. Focusing on our experience in IP, we describe how competency-based measures, simulation technology and various teaching modalities contribute to a more uniform learning environment in which patients do not suffer the burdens of procedure-related training.

Outcomes of an initiative to improve inpatient safety of small bore thoracostomy tube insertion.

BACKGROUND: Intercostal chest catheter (ICC) insertion is a common hospital procedure with attendant risks including life-threatening complications such as pneumothorax and visceral damage. AIM: To investigate the effect of a quality improvement (QI) initiative on complications associated with inpatient thoracostomy tube insertion. METHODS: Following an audit of ICC complications in inpatients over a 2-year period we implemented a comprehensive QI programme. This involved formal training in and mandatory use of thoracic ultrasound, standardisation of the procedure and documentation, a dedicated procedure room with nurses trained in assisting ICC insertion and senior supervision for medical staff. An audit over 2 years post-implementation of the QI protocol was compared with pre-implementation results. RESULTS: A total of 103 cases were reviewed pre-implementation and 105 cases were reviewed post-implementation of the QI programme. All procedures following the QI initiative were image guided compared to 23.3% of cases pre-implementation. The rate of developing a pneumothorax requiring intervention post-implementation was less than pre-implementation (1.9% vs 5.8% (P = 0.023). Post-implementation, there were no instances of dry taps, viscera perforation, clinically significant bleeding or wrong side ICC insertion and documentation improved. CONCLUSION: QI initiative applied to thoracostomy tube insertion in hospital inpatients can reduce complications and improve procedure documentation.

The utility of 3D-printed airway stents to improve treatment strategies for central airway obstructions.

Airway stents are commonly used in the management of patients suffering from central airway obstruction (CAO). CAO may occur directly from airway strictures, obstructing airway cancers, airway fistulas or tracheobronchomalacia, resulting from the weakening and dynamic collapse of the airway wall. Current airway stents are constructed from biocompatible medical-grade silicone or from a nickel-titanium (nitinol) alloy with fixed geometry. The stents are inserted via the mouth during a bronchoscopic procedure. Existing stents have many shortcomings including the development of obstructing granulation tissue in the weeks and months following placement, mucous build up within the stent, and cough. Furthermore, airway stents are expensive and, if improperly sized for a given airway, may be easily dislodged (stent migration). Currently, in Australia, it is estimated that approximately 12,000 patients will develop CAO annually, many of whom will require airway stenting intervention. Of all stenting procedures, the rate of failure is currently reported to be at 22%. With a growing incidence of lung cancer prevalence globally, the need for updating airway stent technology is now greater than ever and personalizing stents using 3D-printing technology may offer the best chance of addressing many of the current limitations in stent design. This review article will assess what represents the gold standard in stent manufacture with regards to treatment of tracheobronchial CAO, the challenges of current airway stents, and outlines the necessity and challenges of incorporating 3D-printing technology into personalizing airway stents today.

Observational cohort study of outcomes in patients admitted to the intensive care unit for acute exacerbation of chronic obstructive pulmonary disease.

BACKGROUND: Patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) are often referred to the intensive care unit (ICU) for non-invasive respiratory support. AIMS: To describe the characteristics of patients with AECOPD admitted to ICU focusing on the performance of ICU prognostic systems, decisions to limit medical therapy and mortality outcomes. METHODS: Retrospective review of patients admitted between 2009 and 2016, separately in patients with active treatment and limitation or withdrawal of medical therapy. ICU acuity scores, blood gas analyses and ICU, in-hospital and 1-year mortality were analysed using descriptive statistics and logistic regression. RESULTS: A total of 403 patients was studied with an overall ICU mortality of 6.4%. The predicted risk of death in hospital using ICU scoring systems was 19% compared to the observed mortality of 15%. One-year mortality was 34%. Patients with limitation of medical therapy represented 32% of the total cohort and had higher mortality in ICU (13%), in hospital (30%) and at 1-year follow up (53%). Withdrawal of life-sustaining therapy occurred in 4% of patients who all died in ICU. Decreased arterial oxygenation and bicarbonate concentration as well as increased arterial carbon dioxide levels were overall associated with an increased likelihood of in-hospital mortality but no independent predictors of 1-year mortality were identified. CONCLUSION: In patients admitted to ICU for AECOPD, limitations of medical therapy are frequent and associated with significant mortality. Involving palliative care in addition to respiratory physicians and intensivists in the management of AECOPD patients admitted to ICU needs to be explored further.

Thoracic ultrasound recognition of competence: A position paper of the Thoracic Society of Australia and New Zealand.

The ability to perform bedside thoracic ultrasound is increasingly recognized as an essential skill for thoracic clinicians, extending the clinical examination and aiding diagnostic and therapeutic procedures. Thoracic ultrasound reduces complications and increases success rates when used prior to thoracentesis or intercostal chest tube insertion. It is increasingly difficult to defend performing these procedures without real or near-real time image guidance. To assist thoracic physicians and others achieve and demonstrate thoracic ultrasound competence, the Interventional Pulmonology Special Interest Group (IP-SIG) of the Thoracic Society of Australia and New Zealand (TSANZ) has developed a new pathway with four components: (i) completion of an approved thoracic ultrasound theory and hands-on teaching course. (ii) A log of at least 40 relevant scans. (iii) Two formative assessments (following 5-10 scans and again after 20 scans) using the Ultrasound-Guided Thoracentesis Skills and Tasks Assessment Tool (UG-STAT). (iv) A barrier assessment (UG-STAT, pass score of 90%) by an accredited assessor not directly involved in the candidate's training. Upon completion of these requirements a candidate may apply to the TSANZ for recognition of competence. This pathway is intended to provide a regional standard for thoracic ultrasound training.

Golgi proteins in circulating human platelets are distributed across non-stacked, scattered structures.

Platelets are small, anucleate cell fragments that are central to hemostasis, thrombosis, and inflammation. They are derived from megakaryocytes from which they inherit their organelles. As platelets can synthesize proteins and contain many of the enzymes of the secretory pathway, one might expect all mature human platelets to contain a stacked Golgi apparatus, the central organelle of the secretory pathway. By thin section electron microscopy, stacked membranes resembling the stacked Golgi compartment in megakaryocytes and other nucleated cells can be detected in both proplatelets and platelets. However, the incidence of such structures is low and whether each and every platelet contains such a structure remains an open question. By single-label, immunofluorescence staining, Golgi glycosyltransferases are found within each platelet and map to scattered structures. Whether these structures are positive for marker proteins from multiple Golgi subcompartments remains unknown. Here, we have applied state-of-the-art techniques to probe the organization state of the Golgi apparatus in resting human platelets. By the whole cell volume technique of serial-block-face scanning electron microscopy (SBF-SEM), we failed to observe stacked, Golgi-like structures in any of the 65 platelets scored. When antibodies directed against Golgi proteins were tested against HeLa cells, labeling was restricted to an elongated juxtanuclear ribbon characteristic of a stacked Golgi apparatus. By multi-label immunofluorescence microscopy, we found that each and every resting human platelet was positive for cis, trans, and trans Golgi network (TGN) proteins. However, in each case, the proteins were found in small puncta scattered about the platelet. At the resolution of deconvolved, widefield fluorescence microscopy, these proteins had limited tendency to map adjacent to one another. When the results of 3D structured illumination microscopy (3D SIM), a super resolution technique, were scored quantitatively, the Golgi marker proteins failed to map together indicating at the protein level considerable degeneration of the platelet Golgi apparatus relative to the layered stack as seen in the megakaryocyte. In conclusion, we suggest that these results have important implications for organelle structure/function relationships in the mature platelet and the extent to which Golgi apparatus organization is maintained in platelets. Our results suggest that Golgi proteins in circulating platelets are present within a series of scattered, separated structures. As separate elements, selective sets of Golgi enzymes or sugar nucleotides could be secreted during platelet activation. The establishment of the functional importance, if any, of these scattered structures in sequential protein modification in circulating platelets will require further research.

Atrial Fibrillation and Sleep Apnoea: Guilt by Association?

Atrial fibrillation (AF) and obstructive sleep apnoea (OSA) are both common, often underdiagnosed conditions with serious sequelae. An association between these two conditions has been recognised but the nature of this relationship remains a topic of active debate. Despite that lack of strong, randomised controlled trials, there is a considerable body of data indicating that not only does untreated OSA provide the substrates and triggers for AF but that OSA, itself, is also a therapeutic target for the management of cardiovascular disease in general and of AF in particular.

Evaluation of Transbronchial Lung Cryobiopsy Size and Freezing Time: A Prognostic Animal Study.

BACKGROUND: Transbronchial lung biopsy using a cryoprobe is a novel way of sampling lung parenchyma. Correlation of freezing time with biopsy size and complications has not been evaluated in vivo. OBJECTIVES: The primary aim of the study is to evaluate the correlation between transbronchial cryobiopsy freezing time and size. The secondary aims are to evaluate histological quality of the biopsy and evaluate procedure-associated complications. METHODS: Transbronchial lung cryobiopsies were obtained from two anaesthetised sheep using a 1.9-mm cryoprobe inserted into a flexible bronchoscope under fluoroscopic guidance. Freezing times ranged from 1 to 6 s (n = 49). The cryobiopsies were evaluated histologically with respect to their size and quality. Complications of bleeding and pneumothorax were recorded. RESULTS: The mean cross-sectional area of the cryobiopsy ranged from 4.7 ± 2.1 to 15.7 ± 15.3 mm2. There was a significant positive correlation between increasing freezing time and cryobiopsy cross-sectional area (p = 0.028). All biopsies contained lung tissue with preserved parenchyma. Crush and freeze artefacts were not observed and tissue architecture was intact in all specimens. Small blood vessels and terminal bronchioles were observed in 88% of specimens. All cryobiopsies caused nil or mild haemorrhage with the exception of only 1 episode of severe haemorrhage at 6 s freezing time. Pneumothoraces occurred at 2, 5 and 6 s freezing time and required chest tube insertion. The most significant haemorrhage and pneumothoraces occurred at 5 and 6 s. Our results suggest an initial freezing time of 3 s can provide the maximal biopsy size while minimising major complications. CONCLUSION: The optimal transbronchial cryobiopsy freezing time is initially 3 s. This time is associated with minimal complications and large artefact-free biopsies.

The histopathological spectrum and molecular changes associated with KRAS G12C mutation in non-small cell lung carcinoma.

KRAS G12C is the most common KRAS mutation in non-small cell lung carcinoma (NSCLC), for which targeted therapy has recently been developed. From the 732 cases of NSCLC that underwent next-generation sequencing at the Department of Anatomical Pathology, Liverpool Hospital, between July 2021 and May 2023, we retrieved 83 (11%) consecutive cases of KRAS G12C mutated NSCLC, and analysed their clinical, pathological, and molecular features. Of the 83 cases of KRAS G12C mutated NSCLC, there were 46 (55%) men and 37 (45%) women, with mean age of 72 years. Of the 49 cases with known clinical information, 94% were current or ex-smokers, and 49% were stage IV at diagnosis with median survival of 12 months. Sixty-three percent were histology cases and the remainder were cytology cases. Eighty-two percent were non-mucinous adenocarcinomas, with conventional histology including lepidic, acinar, solid, single cells and micropapillary patterns, and 62% were poorly differentiated. There were five (6%) cases of mucinous adenocarcinoma, one case of pleomorphic carcinoma and one case of high-grade fetal adenocarcinoma. TTF1 was positive in the majority (89%) of cases. Nineteen (23%) cases had TP53 co-mutation, and these cases had trends towards higher PD-L1 expression, poor differentiation, and presentation as stage IV disease, but the differences were not statistically significant. KRAS G12C mutated NSCLCs almost exclusively occurred in smokers and were mostly non-mucinous adenocarcinomas with conventional histological patterns which ranged from well to poorly differentiated. Around a quarter had TP53 co-mutation, the histological impacts and immune profile of which need to be assessed in a larger study.

Evaluation of Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration (EBUS-TBNA) Samples from Advanced Non-Small Cell Lung Cancer for Whole Genome, Whole Exome and Comprehensive Panel Sequencing.

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is often the only source of tumor tissue from patients with advanced, inoperable lung cancer. EBUS-TBNA aspirates are used for the diagnosis, staging, and genomic testing to inform therapy options. Here we extracted DNA and RNA from 220 EBUS-TBNA aspirates to evaluate their suitability for whole genome (WGS), whole exome (WES), and comprehensive panel sequencing. For a subset of 40 cases, the same nucleic acid extraction was sequenced using WGS, WES, and the TruSight Oncology 500 assay. Genomic features were compared between sequencing platforms and compared with those reported by clinical testing. A total of 204 aspirates (92.7%) had sufficient DNA (100 ng) for comprehensive panel sequencing, and 109 aspirates (49.5%) had sufficient material for WGS. Comprehensive sequencing platforms detected all seven clinically reported tier 1 actionable mutations, an additional three (7%) tier 1 mutations, six (15%) tier 2-3 mutations, and biomarkers of potential immunotherapy benefit (tumor mutation burden and microsatellite instability). As expected, WGS was more suited for the detection and discovery of emerging novel biomarkers of treatment response. WGS could be performed in half of all EBUS-TBNA aspirates, which points to the enormous potential of EBUS-TBNA as source material for large, well-curated discovery-based studies for novel and more effective predictors of treatment response. Comprehensive panel sequencing is possible in the vast majority of fresh EBUS-TBNA aspirates and enhances the detection of actionable mutations over current clinical testing.

Vomiting and Abdominal Pain in a 5-Year-Old Male.

This case describes small bowel obstruction secondary to a Meckel's Diverticulum in a 5-year-old male patient with a chief complain of abdominal pain and vomiting. We review the pathophysiology, diagnosis, and management of Meckel's Diverticulum. This case report highlights the importance of considering a broad differential diagnosis during a clinical workup.