Using cryoprobes of different sizes combined with cone-beam computed tomography-derived augmented fluoroscopy and endobronchial ultrasound to diagnose peripheral pulmonary lesions: a propensity-matched study.

BACKGROUND: Endobronchial ultrasound (EBUS) and cone-beam computed tomography-derived augmented fluoroscopy (CBCT-AF) are utilized for the diagnosis of peripheral pulmonary lesions (PPLs). Combining them with transbronchial cryobiopsy (TBC) can provide sufficient tissue for genetic analysis. However, cryoprobes of different sizes have varying degrees of flexibility, which can affect their ability to access the target bronchus and potentially impact the accuracy. The aim of this study was to compare the diagnostic efficacy of cryoprobes of varying sizes in CBCT-AF and EBUS for the diagnosis of PPLs. METHODS: Patients who underwent endobronchial ultrasound-guided transbronchial biopsy (EBUS-TBB) and TBC combined with CBCT-AF for PPLs diagnosis between January 2021 and May 2022 were included. Propensity score matching and competing-risks regression were utilized for data analysis. Primary outcome was the diagnostic accuracy of TBC. RESULTS: A total of 284 patients underwent TBC, with 172 using a 1.7-mm cryoprobe (1.7 group) and 112 using a 1.1-mm cryoprobe (1.1 group). Finally, we included 99 paired patients following propensity score matching. The diagnostic accuracy of TBC was higher in the 1.1 group (80.8% vs. 69.7%, P = 0.050), with a similar rate of complications. Subgroup analysis also revealed that the 1.1 group had better accuracy when PPLs were located in the upper lobe (85.2% vs. 66.1%, P = 0.020), when PPLs were smaller than 20 mm (78.8% vs. 48.8%, P = 0.008), and when intra-procedural CBCT was needed to be used (79.5% vs. 42.3%, P = 0.001). TBC obtained larger specimens than TBB in both groups. There is still a trend of larger sample size obtained in the 1.7 group, but there is no statistically different between our two study groups (40.8 mm2 vs. 22.0 mm2, P = 0.283). CONCLUSIONS: The combination of TBC with CBCT-AF and EBUS is effective in diagnosing PPLs, and a thin cryoprobe is preferred when the PPLs located in difficult areas.

Utility of bronchoscopically obtained frozen cytology pellets for next-generation sequencing.

BACKGROUND: Next-generation sequencing (NGS) is essential for lung cancer treatment. It is important to collect sufficient tissue specimens, but sometimes we cannot obtain large enough samples for NGS analysis. We investigated the yield of NGS analysis by frozen cytology pellets using an Oncomine Comprehensive Assay or Oncomine Precision Assay. METHODS: We retrospectively enrolled patients with lung cancer who underwent bronchoscopy at Kobe University Hospital and were enrolled in the Lung Cancer Genomic Screening Project for Individualized Medicine. We investigated the amount of extracted DNA and RNA and determined the NGS success rates. We also compared the amount of DNA and RNA by bronchoscopy methods. To create the frozen cytology pellets, we first effectively collected the cells and then quickly centrifuged and cryopreserved them. RESULTS: A total of 132 patients were enrolled in this study between May 2016 and December 2022; of them, 75 were subjected to frozen cytology pellet examinations and 57 were subjected to frozen tissue examinations. The amount of DNA and RNA obtained by frozen cytology pellets was nearly equivalent to frozen tissues. Frozen cytology pellets collected by endobronchial ultrasound-guided transbronchial needle aspiration yielded significantly more DNA than those collected by transbronchial biopsy methods. (P < 0.01) In RNA content, cytology pellets were not inferior to frozen tissue. The success rate of NGS analysis with frozen cytology pellet specimens was comparable to the success rate of NGS analysis with frozen tissue specimens. CONCLUSIONS: Our study showed that frozen cytology pellets may have equivalent diagnostic value to frozen tissue for NGS analyses. Bronchial cytology specimens are usually used only for cytology, but NGS analysis is possible if enough cells are collected to create pellet specimens. In particular, the frozen cytology pellets obtained by endobronchial ultrasound-guided transbronchial needle aspiration yielded sufficient amounts of DNA. TRIAL REGISTRATION: This was registered with the University Medical Hospital Information Network in Japan (UMINCTR registration no. UMIN000052050).

Diagnostic value of the Xpert MTB/RIF assay combined with endobronchial ultrasonography with a guide sheath for peripheral nodular pulmonary tuberculosis.

BACKGROUND: The diagnosis of peripheral isolated nodular lesions that are suspected as pulmonary tuberculosis (PTB) is challenging, which are not easily accessible via conventional bronchoscopy. This study evaluated the combined use of Xpert MTB/RIF assay and endobronchial ultrasonography with a guide sheath (EBUS-GS) for detecting MTB infection in peripheral lung bands, for early detection of PTB. METHODS: The clinical data of 232 patients with suspected peripheral nodular PTB who underwent EBUS-GS between June 2020 and October 2023 were retrospectively reviewed. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the curve (AUC) of acid-fast bacilli smear, culture, Xpert MTB/RIF assay, and pathological examination were calculated. To assess diagnostic accuracy, the results of the four methods were directly compared with the final clinical diagnosis. RESULTS: In total, 146 and 86 patients were clinically diagnosed with peripheral nodular PTB and non-PTB, respectively. The sensitivity, specificity, PPV, NPV, and AUC values of combined Xpert MTB/RIF assay and EBUS-GS were 47.26%, 100.0%, 100.0%, 52.76%, and 0.74; those of acid-fast bacilli smear were 8.22%, 97.67%, 85.71%, 38.53%, and 0.53; those of culture were 31.51%, 100.0%, 100.0%, 46.24%, and 0.66; and those of pathological examination were 23.97%, 97.67%, 94.59%, 43.08%, and 0.61, respectively. CONCLUSION: The diagnostic accuracy of the combined Xpert MTB/RIF assay and EBUS-GS was significantly better than that of other conventional tests. Hence, this novel technique can be routinely applied for diagnosing and managing peripheral nodular PTB.

Diagnostic efficacy of endobronchial ultrasound-guided transbronchoscopic lung biopsy for identifying tuberculous nodules.

BACKGROUND: Microbiological diagnosis of pulmonary tuberculosis (PTB) is hampered by a low pathogen burden, low compliance and unreliable sputum sampling. Although endobronchial ultrasound-guided transbronchoscopic lung biopsy (EBUS-TBLB) has been found to be useful for the assessment of intrapulmonary nodules in adults, few data are available for the clinical diagnosis of pulmonary tuberculosis. Here, we evaluated EBUS-TBLB as a diagnostic procedure in adult patients with radiologically suspected intrapulmonary tuberculous nodules. METHODS: This was a retrospective analysis of patients admitted with pulmonary nodules between January 2022 and January 2023 at Hangzhou Red Cross Hospital. All patients underwent EBUS-TBLB, and lung biopsy samples were obtained during hospitalization. All samples were tested for Mycobacterium tuberculosis using acid‒fast smears, Bactec MGIT 960, Xpert MTB/RIF, next-generation sequencing (NGS), and DNA (TB‒DNA) and RNA (TB‒RNA). The concordance between different diagnostic methods and clinical diagnosis was analysed via kappa concordance analysis. The diagnostic efficacy of different diagnostic methods for PTB was analysed via ROC curve. RESULTS: A total of 107 patients were included in this study. Among them, 86 patients were diagnosed by EBUS-TBLB, and the overall diagnostic rate was 80.37%. In addition, 102 enrolled patients had benign lesions, and only 5 were diagnosed with lung tumours. Univariate analysis revealed that the diagnostic rate of EBUS-TBLB in pulmonary nodules was related to the location of the probe. The consistency analysis and ROC curve analysis revealed that NGS had the highest concordance with the clinical diagnosis results (agreement = 78.50%, κ = 0.558) and had the highest diagnostic efficacy for PTB (AUC = 0.778). In addition, Xpert MTB/RIF + NGS had the highest concordance with the clinical diagnosis results (agreement = 84.11%, κ = 0.667) and had the highest efficacy in the diagnosis of PTB (AUC = 0.826). CONCLUSION: EBUS-TBLB is a sensitive and safe method for the diagnosis of pathological pulmonary nodules. Xpert MTB/RIF combined with NGS had the highest diagnostic efficacy and can be used in the initial diagnosis of PTB.

Franseen needle in endobronchial ultrasound-guided transbronchial needle aspiration: a phase II prospective study.

BACKGROUND: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has been used to diagnose and stage lung cancer. Acquire™ Pulmonary and Expect™ Pulmonary dedicated EBUS-TBNA needles were introduced as the Franseen and Lancet needles, respectively. It is still unclear whether the Franseen or Lancet needles yield a higher quality specimen especially focusing on next-generation sequencing-based molecular testing. METHODS: A single-center, prospective study performed at the Chiba University Hospital randomly assigned patients to two groups: Group A, wherein the first and second EBUS-TBNA were performed using Lancet and Franseen needles, respectively, and Group B, wherein the first and second EBUS-TBNA were performed using Franseen and Lancet needles, respectively. Each specimen was compared and analyzed pathologically. The primary outcome was the histological tissue area except blood clot and the cellularity of each sample. We also examined the success rate of molecular testing. RESULTS: Twelve patients who underwent EBUS-TBNA between November 2022 and February 2023 were enrolled in this study. The tissue area of the specimens obtained by the Franseen and Lancet needles was 13.3 ± 6.4 mm2 and 10.6 ± 6.3 mm2, respectively (P = .355). The tumor cellularity in the specimens obtained using the Franseen and Lancet needles was 54.0 ± 30.3 and 46.2 ± 36.3%, respectively (P = .608). The success rate of molecular testing using the single-pass sample by Franseen needle was 85.7 and 57.1% by Lancet needle. No serious complications were reported. CONCLUSIONS: The Franseen needle tended to show a greater amount of specimen with higher tumor cellularity than the Lancet needle which may contribute higher success rate of molecular testing. Further studies must be conducted to validate the results of this study. KEY FINDINGS: What is known and what is new?  What is the implication, and what should change now?

Next-generation sequencing using tissue specimen collected with a 1.1 mm-diameter cryoprobe in patients with lung cancer.

BACKGROUND AND OBJECTIVE: Next-generation sequencing (NGS) analysis is considered standard for lung cancer diagnosis in clinical practice. Little is known about the feasibility of NGS using tumour tissue sampled with a 1.1 mm-diameter cryoprobe. We aimed to investigate the suitability of specimens obtained by transbronchial cryobiopsy (TBC) using a 1.1 mm-diameter cryoprobe for NGS analysis. METHODS: Patients with lung cancer who underwent TBC using a 1.1 mm-diameter cryoprobe for NGS testing between October 2020 and April 2023 were enrolled. A 4.0- or 3.0 mm-diameter bronchoscope with radial probe endobronchial ultrasound and virtual bronchoscopic navigation was used to detect peripheral lung lesions. All procedures were performed under fluoroscopic guidance. Data were analysed retrospectively. RESULTS: A total of 56 patients underwent TBC using a 1.1 mm cryoprobe for NGS testing, during the study period. Most patients (98%) were in the advanced stage of lung cancer (recurrent or inoperable disease of stages III or IV). The diagnostic yield of NGS for DNA and RNA sequencing was 95% each (53 of 56). Moderate bleeding was noted in three patients (5%) and none of the study patients developed life-threatening complications, such as pneumothorax or lung infection. CONCLUSION: TBC using a 1.1 mm-diameter cryoprobe is a useful and safe tool for NGS analysis, for both DNA and RNA sequencing.

Comparison of the specimen quality of endobronchial ultrasound-guided intranodal forceps biopsy using standard-sized forceps versus mini forceps for lung cancer: A prospective study.

BACKGROUND AND OBJECTIVE: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a diagnostic procedure with adequate performance; however, its ability to provide specimens of sufficient quality and quantity for treatment decision-making in advanced-stage lung cancer may be limited, primarily due to blood contamination. The use of a 0.96-mm miniforceps biopsy (MFB) permits true histological sampling, but the resulting small specimens are unsuitable for the intended applications. Therefore, we introduced a 1.9-mm standard-sized forceps biopsy (SFB) and compared its utility to that of MFB. METHODS: We prospectively enrolled patients from three institutions who presented with hilar/mediastinal lymphadenopathy and suspected advanced-stage lung cancer, or those who were already diagnosed but required additional tissue specimens for biomarker analysis. Each patient underwent MFB followed by SFB three or four times through the tract created by TBNA using a 22-gauge needle on the same lymph node (LN). Two pathologists assessed the quality and size of each specimen using a virtual slide system, and diagnostic performance was compared between the MFB and SFB groups. RESULTS: Among the 60 enrolled patients, 70.0% were diagnosed with adenocarcinoma. The most frequently targeted sites were the lower paratracheal LNs, followed by the interlobar LNs. The diagnostic yields of TBNA, MFB and SFB were 91.7%, 93.3% and 96.7%, respectively. The sampling rate of high-quality specimens was significantly higher in the SFB group. Moreover, the mean specimen size for SFB was three times larger than for MFB. CONCLUSION: SFB is useful for obtaining sufficient qualitative and quantitative specimens.

EBUS-TBNA for mediastinal staging of centrally located T1N0M0 non-small cell lung cancer clinically staged with PET/CT.

BACKGROUND AND OBJECTIVE: To evaluate the diagnostic accuracy and clinical usefulness of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for mediastinal staging of centrally located T1N0M0 non-small cell lung cancer (NSCLC) clinically staged with positron emission tomography/computed tomography (PET/CT). METHODS: We conducted a study that included patients with centrally located T1N0M0 NSCLC, clinically staged with PET/CT who underwent EBUS-TBNA for mediastinal staging. Patients with negative EBUS-TBNA underwent mediastinoscopy, video-assisted mediastinoscopic lymphadenectomy (VAMLA) and/or lung resection with systematic nodal dissection, that were considered the gold standard. The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), overall accuracy of EBUS-TBNA for diagnosing mediastinal metastases (N2 disease) and the number needed to treat (NNT: number of patients needed to undergo EBUS-TBNA to avoid a case of pathologic N2 disease after resection) were calculated. RESULTS: One-hundred eighteen patients were included. EBUS-TBNA proved N2 disease in four patients. In the remaining 114 patients who underwent mediastinoscopy, VAMLA and/or resection there were two cases of N2 (N2 prevalence 5.1%). The sensitivity, specificity, NPV, PPV and overall accuracy for diagnosing mediastinal metastases (N2 disease) were of 66%, 100%, 98%, 100% and 98%, respectively. The NNT was 31 (95% CI: 15-119). CONCLUSION: EBUS-TBNA in patients with central clinically staged T1N0M0 NSCLC presents a good diagnostic accuracy for mediastinal staging, even in a population with low prevalence of N2 disease. Therefore, its indication should be considered in the management of even these early lung cancers.

Feasibility and Safety of Transesophageal Mediastinal Cryobiopsy in the Diagnosis of Mediastinal Pathologies.

INTRODUCTION: Endobronchial ultrasound-guided transbronchial needle aspiration remains the gold standard for the diagnosis of mediastinal pathologies. Its greatest limitation has been the low diagnostic yield in lymphoproliferative disorders as well as insufficient samples for molecular testing. Transesophageal examinations using an EBUS scope have helped increase the diagnostic yield by allowing for additional biopsies of paraesophageal and intra-abdominal lesions. Similarly, the novel approach of transbronchial mediastinal cryobiopsy has further increased the yield by providing larger and better-preserved biopsies. Both complimentary techniques have shown great individual feasibility and safety. However, the feasibility of transesophageal cryobiopsies in the evaluation of mediastinal pathologies remains a subject of debate. AIM: The aim of the study was to investigate the safety and feasibility of transesophageal EBUS-guided mediastinal cryobiopsies performed at our center. METHODS: We conducted a retrospective review of 30 patients who underwent mediastinal cryobiopsy through the esophagus at our institution between October 2023 and March 2024. Data on patient demographics, diagnostic yield, and complications were collected and analyzed. RESULTS: The mean patient age was 43 years, with a gender distribution of 60% male and 40% female. The primary indications included suspicion of lymphoproliferative disorders, suspected sarcoidosis, and malignancies with paraesophageal lesions. The overall diagnostic yield was 93%. No major complications were noted in any of the patients. CONCLUSION: Transesophageal mediastinal cryobiopsy appears to be a promising complimentary technique for mediastinal evaluation with a relatively high diagnostic yield and favorable safety profile. However, further studies with larger cohorts are warranted to validate the findings at our institution.

Comparison between Endobronchial Ultrasound-Guided Transbronchial Node Biopsy and Transbronchial Needle Aspiration: A Meta-Analysis.

INTRODUCTION: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) can be limited by the inadequacy of intact tissues, especially in patients with lymphoma, sarcoidosis, and lymph node tuberculosis. A novel technique called transbronchial node biopsy (TBNB) by forceps or cryoprobe has been proposed and studied to improve specimen quality and diagnostic yield. We performed a systematic review of studies describing the safety and sensitivity of EBUS-TBNB versus EBUS-TBNA in diagnosing intrathoracic lymphadenopathy/masses. METHODS: We systematically searched MEDLINE, Embase, Cochrane, and China National Knowledge Infrastructure to identify studies focusing on the application of EBUS-TBNB for diagnosis of intrathoracic lymphadenopathy. The quality of each study was evaluated using the QUADAS-2 tool. Using inverse-variance (I-V) weighting, we performed a meta-analysis of diagnostic yield estimations. We also reviewed the complications related to the procedure. RESULTS: Thirteen studies were included in the final analysis. The meta-analysis yielded a pooled overall diagnostic yield of 77.80% (939/1,207) for EBUS-TBNA and 86.01% (834/958) for EBUS-TBNB, with an inverse-variance-weighted odds ratio of 3.13 (95% confidence interval [CI], 1.61-6.01; p = 0.0008) and I2 of 82%. The pooled diagnostic yield of EBUS-TBNB versus EBUS-TBNA for the diagnosis of malignancy (including primary lung cancer and extrapulmonary malignancy) was 84.53% (590/698) for EBUS-TBNA and 90.84% (476/524) for EBUS-TBNB, with an I-V-weighted OR of 2.33 (95% CI, 1.15-4.74; p = 0.02) and I2 of 64%. The pooled diagnostic yield of EBUS-TBNB versus EBUS-TBNA for the diagnosis of benignancy was 71.19% (252/354) for EBUS-TBNA and 86.62% (233/269) for EBUS-TBNB, with an I-V-weighted OR of 4.39 (95% CI, 2.00-9.65; p = 0.002) and I2 of 59%. The overall complications included bleeding (n = 11, 0.90%), pneumomediastinum (n = 6, 0.49%), pneumothorax (n = 6, 0.49%), pneumonia (n = 4, 0.33%), respiratory failure (n = 1, 0.08%), and haemoptysis (n = 1, 0.08%). The funnel plot analysis illustrated no major publication bias. CONCLUSIONS: EBUS-TBNB improves the overall diagnostic yield of sampling intrathoracic lymphadenopathy and mass lesions relative to EBUS-TBNA. The complication rate of EBUS-TBNB is higher than that of EBUS-TBNA but reportedly lower than that of surgical biopsies.

A Novel Procedure for Endobronchial Ultrasound-Guided Transbronchial Mediastinal Cryobiopsy with a Puncture Dilation Catheter.

INTRODUCTION: Endobronchial ultrasound (EBUS)-guided transbronchial mediastinal cryobiopsy (TBMC) is increasingly used to diagnose mediastinal lymphadenopathy. Various methods have been used to create a tunnel between the airway wall and the lesions for this procedure, such as electrocautery and penetration with the sheath of the needle for EBUS-transbronchial fine needle aspiration. However, those methods are complex. CASE PRESENTATION: We developed a new technique called EBUS-TBMC via a tunnel, and we used it in four cases of mediastinal and/or hilar lymphadenopathy. We used a puncture dilation catheter to create a tunnel between the airway wall and the target lymph node. The cryoprobe was introduced to the target lymph node and cooled with liquid carbon dioxide for 5-9 s. The probe was subsequently pulled out with the samples to complete the EBUS-TBMC via a tunnel. A definite diagnosis was made based on pathological examination of the samples obtained in all four cases. After the procedure, none of the patients experienced moderate to severe bleeding, pneumothorax, pneumomediastinum, or other adverse events. CONCLUSION: EBUS-TBMC via a tunnel is a feasible and convenient procedure for the performance of TBMC. Further studies are required to evaluate the safety and efficacy of EBUS-TBMC via a tunnel.

Endobronchial Ultrasound-Guided Transbronchial Mediastinal Cryobiopsy versus Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration for Mediastinal Disorders: A Meta-Analysis.

INTRODUCTION: Endobronchial ultrasound-guided transbronchial mediastinal cryobiopsy (EBUS-TMC), a novel technique, has been reported to improve the diagnostic value of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for mediastinal lesions in recent studies. Current literature suggests that this procedure has greater diagnostic efficacy compared to conventional EBUS-TBNA. This systematic review and meta-analysis aimed to evaluate the diagnostic yield and complications associated with EBUS-TMC in comparison to EBUS-TBNA, thereby exploring the potential of this novel technique in enhancing the diagnostic utility for mediastinal lesions. METHODS: A comprehensive literature review was conducted by searching the PubMed, Embase, and Google Scholar databases for articles published from inception to December 31, 2023. The objective of this review was to evaluate the utilization of EBUS-TMC in diagnosing mediastinal disease, while also assessing the quality of each study using the QUADAS-2 tool. The diagnostic yield estimates were subjected to a meta-analysis utilizing inverse variance weighting. Furthermore, a comprehensive analysis of the complications associated with this procedure was performed. RESULTS: The meta-analysis included 10 studies involving a total of 538 patients. The findings of the meta-analysis demonstrated that EBUS-TMC yielded an overall diagnostic rate of 89.59% (482/538), while EBUS-TBNA yielded a rate of 77.13% (415/538). The calculated inverse variance-weighted odds ratio was 2.63 (95% confidence interval, 1.86-3.72; p < 0.0001), and I2 value was 11%, indicating a statistically significant difference between the two techniques. The associated complications consisted of pneumothorax, pneumomediastinum, mediastinitis, and bleeding, with an incidence of 0.74% (4/538), 0.37% (2/538), 0.0% (0/538), and 1.12% (6/538), respectively. Moreover, the funnel plot displayed no discernible publication bias. Further subgroup analysis revealed a notable improvement in the diagnosis value for lymphoma (86.36% vs. 27.27%, p = 0.0006) and benign disorder (87.62% vs. 60.00%, p < 0.0001). CONCLUSION: This review of the current available studies indicated that EBUS-TMC enhanced overall diagnostic yields compared to EBUS-TBNA, particularly for diagnosing benign disease and lymphoma. This procedure was not associated with any serious complications.

Successful Retrieval of a Broken Aspiration Needle Penetrated into the Right Pulmonary Artery: A Case Report with Experience Sharing.

INTRODUCTION: Endobronchial ultrasound-guided transbronchial needle aspiration is increasingly used as a minimally invasive procedure in clinical settings. It is generally regarded as a safe procedure with high diagnostic accuracy. However, a complication involving a needle fracture that penetrated a nearby artery has not been reported during this procedure. CASE PRESENTATION: A male patient, 58 years of age, underwent endobronchial ultrasound-guided transbronchial needle aspiration for a mediastinal lymph node biopsy at a local hospital. The aspiration needle fractured and penetrated from the right middle segmental bronchus into the right pulmonary artery. The patient was then transferred to our hospital. After conducting repeated chest imaging examinations to confirm the presence of the foreign body and holding multidisciplinary team consultations, we first inserted a deflated balloon catheter near the puncture site in the right middle segmental bronchus. Following the needle retrieval through a flexible bronchoscope, the balloon catheter was inflated to ensure local hemostasis. Follow-up evaluations revealed no further complications for this patient. CONCLUSION: Intragenic vascular injury can occur during endobronchial ultrasound-guided transbronchial needle aspiration. Careful pre-procedure preparations should be planned to minimize complications. In patients experiencing complications due to needle penetration, consultation and coordination with a multidisciplinary team are essential to ensure the safe retrieval of the broken needle.

Endobronchial Ultrasound-Based Support Vector Machine Model for Differentiating between Benign and Malignant Mediastinal and Hilar Lymph Nodes.

INTRODUCTION: The aim of the study was to establish an ultrasonographic radiomics machine learning model based on endobronchial ultrasound (EBUS) to assist in diagnosing benign and malignant mediastinal and hilar lymph nodes (LNs). METHODS: The clinical and ultrasonographic image data of 197 patients were retrospectively analyzed. The radiomics features extracted by EBUS-based radiomics were analyzed by the least absolute shrinkage and selection operator. Then, we used a support vector machine (SVM) algorithm to establish an EBUS-based radiomics model. A total of 205 lesions were randomly divided into training (n = 143) and validation (n = 62) groups. The diagnostic efficiency was evaluated by receiver operating characteristic (ROC) curve analysis. RESULTS: A total of 13 stable radiomics features with non-zero coefficients were selected. The SVM model exhibited promising performance in both groups. In the training group, the SVM model achieved an ROC area under the curve (AUC) of 0.892 (95% CI: 0.885-0.899), with an accuracy of 85.3%, sensitivity of 93.2%, and specificity of 79.8%. In the validation group, the SVM model had an ROC AUC of 0.906 (95% CI: 0.890-0.923), an accuracy of 74.2%, a sensitivity of 70.3%, and a specificity of 74.1%. CONCLUSION: The EBUS-based radiomics model can be used to differentiate mediastinal and hilar benign and malignant LNs. The SVM model demonstrated excellent potential as a diagnostic tool in clinical practice.

Ultrathin Bronchoscopy Without Virtual Navigation for Diagnosis of Peripheral Lung Lesions.

BACKGROUND: The increasing incidence of encountering lung nodules necessitates an ongoing search for improved diagnostic procedures. Various bronchoscopic technologies have been introduced or are in development, but further studies are needed to define a method that fits best in clinical practice and health care systems. RESEARCH QUESTION: How do basic bronchoscopic tools including a combination of thin (outer diameter 4.2 mm) and ultrathin bronchoscopes (outer diameter 3.0 mm), radial endobronchial ultrasound (rEBUS) and fluoroscopy perform in peripheral pulmonary lesion diagnosis? STUDY DESIGN AND METHODS: This is a retrospective review of the performance of peripheral bronchoscopy using thin and ultrathin bronchoscopy with rEBUS and 2D fluoroscopy without a navigational system for evaluating peripheral lung lesions in a single academic medical center from 11/2015 to 1/2021. We used a strict definition for diagnostic yield and assessed the impact of different variables on diagnostic yield, specifically after employment of the ultrathin bronchoscope. Logistic regression models were employed to assess the independent associations of the most impactful variables. RESULTS: A total of 322 patients were included in this study. The median of the long axis diameter was 2.2 cm and the median distance of the center of the lesion from the visceral pleural surface was 1.9 cm. Overall diagnostic yield was 81.3% after employment of the ultrathin bronchoscope, with more detection of concentric rEBUS views (93% vs. 78%, p < 0.001). Sensitivity for detecting malignancy also increased from 60.5% to 74.7% (p = 0.033) after incorporating the ultrathin scope into practice, while bronchus sign and peripheral location of the lesion were not found to affect diagnostic yield. Concentric rEBUS view, solid appearance, upper/middle lobe location and larger size of the nodules were found to be independent predictors of successful achievement of diagnosis at bronchoscopy. INTERPRETATION: This study demonstrates a high diagnostic yield of biopsy of lung lesions achieved by utilization of thin and ultrathin bronchoscopes. Direct visualization of small peripheral airways with simultaneous rEBUS confirmation increased localization rate of small lesions in a conventional bronchoscopy setting without virtual navigational planning.

Adenocarcinoma originating in the anterior mediastinum diagnosed by endobronchial ultrasound-guided transbronchial cryobiopsy: a case report.

BACKGROUND: Endobronchial ultrasound-guided transbronchial cryobiopsy (EBUS-cryobiopsy) is advantageous for collecting larger specimens with minimal crushing; however, it has not been widely used for mediastinal tumors. CASE PRESENTATION: A 73-year-old woman with a history of left breast cancer underwent surgery followed by radiotherapy. Computed tomography showed a mass in the anterior mediastinum that was in extensive contact with the sternum on the ventral side and partly with the trachea on the dorsal side. Two computed tomography-guided needle biopsies (CTNBs) were performed on the mass; however, a definitive diagnosis was not made because of severe crush artifacts. Subsequently, we performed EBUS-cryobiopsy and safely obtained sufficient specimen volume with minimal crushing. The histopathological diagnosis was adenocarcinoma, with immunobiological features distinct from those of previous breast cancers. Her overall diagnosis was a rare tumor originating in the anterior mediastinum. CONCLUSIONS: EBUS-cryobiopsy can be safely performed in narrow areas surrounded by major blood vessels, and the obtained specimens may be superior to CTNBs for histopathological diagnosis.

Impact of rapid on-site evaluation in expediting the fast investigative lung cancer pathway.

OBJECTIVE: EBUS-TBNA is a method of acquiring tissue samples from intrathoracic lymph nodes and central intrathoracic tumours in patients suspected of having lung cancer. Rapid on-site evaluation (ROSE) denotes assessing tissue samples during EBUS (or bronchoscopy), providing instant feedback on sample adequacy and provisional cytomorphological diagnosis. Sector multidisciplinary team (MDT) discussion can then make informed treatment decisions, with confirmatory immunohistochemistry being finalised before provision of final treatment. Currently, impact of ROSE on length of time patients spend on the lung cancer diagnostic pathway remains unclear. METHODS: We retrospectively evaluated the impact of ROSE on the length of time between patients' EBUS/bronchoscopy procedures and discussion at sector MDT, referred to as time to treatment decision (TTD), at our institution. Additionally, we assessed impact of ROSE on number of passes (number of times nodes/masses were sampled) per procedure. RESULTS: The mean TTD was 77.9% shorter (p = 0.001) with ROSE present than when absent. Patients who received ROSE spend 34.3% less time (p = 0.028) on lung cancer diagnostic pathway overall. There was a significant reduction in number of passes in non-malignant nodes with ROSE present (2.23) than when absent (3.14) (p < 0.001). With ROSE present there was a significantly greater number of passes at malignant sites (5.07) than non-malignant sites (2.23) (p < 0.001). CONCLUSIONS: These findings support conclusions made in our institution's previous study, that utilisation of ROSE reduces TTD. ROSE also allows safe advancement through nodes with low suspicion of malignant involvement, focusing time on sampling nodes/masses of greater suspicion.

TransEBUS: The interpretation of endobronchial ultrasound image using hybrid transformer for differentiating malignant and benign mediastinal lesions.

The purpose of this study is to establish a deep learning automatic assistance diagnosis system for benign and malignant classification of mediastinal lesions in endobronchial ultrasound (EBUS) images. EBUS images are in the form of video and contain multiple imaging modes. Different imaging modes and different frames can reflect the different characteristics of lesions. Compared with previous studies, the proposed model can efficiently extract and integrate the spatiotemporal relationships between different modes and does not require manual selection of representative frames. In recent years, Vision Transformer has received much attention in the field of computer vision. Combined with convolutional neural networks, hybrid transformers can also perform well on small datasets. This study designed a novel deep learning architecture based on hybrid transformer called TransEBUS. By adding learnable parameters in the temporal dimension, TransEBUS was able to extract spatiotemporal features from insufficient data. In addition, we designed a two-stream module to integrate information from three different imaging modes of EBUS. Furthermore, we applied contrastive learning when training TransEBUS, enabling it to learn discriminative representation of benign and malignant mediastinal lesions. The results show that TransEBUS achieved a diagnostic accuracy of 82% and an area under the curve of 0.8812 in the test dataset, outperforming other methods. It also shows that several models can improve performance by incorporating two-stream module. Our proposed system has shown its potential to help physicians distinguishing benign and malignant mediastinal lesions, thereby ensuring the accuracy of EBUS examination.

Machine learning approaches in the interpretation of endobronchial ultrasound images: a comparative analysis.

BACKGROUND: This study explores the application of machine learning (ML) in analyzing endobronchial ultrasound (EBUS) images for the detection of lymph node (LN) malignancy, aiming to augment diagnostic accuracy and efficiency. We investigated whether ML could outperform conventional classification systems in identifying malignant involvement of LNs, based on eight established sonographic features. METHODS: Retrospective data from two tertiary care hospital bronchoscopy units were utilized, encompassing healthcare reports of patients who had undergone EBUS between January 2017 and March 2023. The ML model was trained and tested using MATLAB, with 80% of the data allocated for training/validation, and 20% for testing. Performance was evaluated based on validation and testing accuracy, and receiver operating characteristic curves with comparing trained models and existing classification rules. RESULTS: The study analyzed 992 LNs, with 42.3% malignancy prevalence. Malignant LNs showed characteristic features such as larger size and distinct margins. The fine tuned models achieved testing accuracies of 95.9% and 96.4% for fine Gaussian SVM and KNN, respectively. Corresponding AUROC's were 0.955 and 0.963, outperforming other similar studies and conventional analyses. CONCLUSION: Fine tuned ML applications like SVM and KNN, can significantly enhance the analysis of EBUS images, improving diagnostic accuracy.

Value of adding ultrathin bronchoscopy to thin bronchoscopy for peripheral pulmonary lesions: A multicentre prospective study.

BACKGROUND AND OBJECTIVE: The diagnostic yield of thin bronchoscopy with radial probe endobronchial ultrasound (rEBUS) of peripheral pulmonary lesions into which the rEBUS probe cannot be inserted is unsatisfactory. In such cases, adding ultrathin bronchoscopy may be an option. We evaluated the efficacy of sequential ultrathin bronchoscopy for peripheral pulmonary lesions into which the rEBUS probe could not be inserted during thin bronchoscopy. METHODS: In this multicentre prospective study, patients with peripheral pulmonary lesions ≤30 mm in diameter underwent rEBUS-guided transbronchial biopsy using a 4.0 mm diameter thin bronchoscope. In patients with lesions into which a rEBUS probe could not be inserted using that bronchoscope, bronchoscopy using a 3.0 mm diameter ultrathin bronchoscope was performed. RESULTS: A total of 342 patients were enrolled and 340 were analysed. Among them, 87 patients with lesions of a median longest diameter of 17.5 mm underwent thin bronchoscopy followed by ultrathin bronchoscopy. Of the 87 patients, the rEBUS probe was successfully inserted into the lesions via the ultrathin bronchoscope in 50 patients (57.5%). Of the 87 patients, the diagnostic yields of thin bronchoscopy and ultrathin bronchoscopy were 12.6% (11 of 87) and 41.4% (36 of 87), respectively (p < 0.001). CONCLUSION: Ultrathin bronchoscopy affords a higher diagnostic yield for lesions into which a rEBUS probe cannot be inserted via a thin bronchoscope.