Endobronchial ultrasonography using a guide sheath technique for diagnosis of peripheral pulmonary lesions

High-efficiency EGFR genotyping using cell-free DNA in bronchial washing fluid

BACKGROUND

EGFR mutation testing is required for treatment of lung adenocarcinoma using epidermal growth factor receptor-tyrosine kinase inhibitor. However, the amounts of tumor tissue or tumor cells obtained by bronchoscopy are often insufficient. Bronchial washing fluid, obtained by lavage with saline after tumor biopsy or brushing, and the supernatant of bronchial washing fluid are thought to contain cell-free DNA that would be potentially applicable for EGFR testing.

METHODS

From among patients with suspected adenocarcinoma or non-small cell lung carcinoma diagnosed from biopsy or surgical specimens at the University of Tsukuba Hospital between 2015 and 2019, cell-free DNAs from 80 specimens of supernatant of bronchial washing fluid (50 with EGFR mutation and 30 with wild type EGFR) and 8 blood serum samples were examined for EGFR mutation using droplet digital PCR.

RESULTS

Among the 50 patients harboring EGFR mutation, the rate of positivity for cell-free DNA extracted from supernatant of bronchial washing fluid was 80% (40/50). In nine of the EGFR mutation-positive cases, tumor cells were not detected by either biopsy or cytology, but the mutation was detected in four cases (4/9, 44%). Comparison of the cell-free DNA mutation detection rate between supernatant of bronchial washing fluid and blood serum in six cases showed that mutations were detected from the former in all cases (6/6, 100%), but from the latter in only one case (1/6, 17%).

CONCLUSIONS

Using supernatant of bronchial washing fluid samples, the detection rate of EGFR mutation was high, and EGFR mutations were detectable even when no tumor cells had been detectable by biopsy or cytology. Supernatant of bronchial washing fluid might be an effective sample source for EGFR mutation testing.

Impact of Cough Severity on the Diagnostic Yield of Endobronchial Ultrasonography Transbronchial Biopsy with Guide Sheath: A Retrospective Observational Study

Bronchoscopy is an invasive procedure, and patient coughing during examination has been reported to cause patient distress. This study aimed to clarify the relationship between cough severity and diagnostic yield of endobronchial ultrasonography with guide sheath transbronchial biopsy (EBUS-GS-TBB). Data of patients who underwent bronchoscopy at Kyorin University Hospital between April 2019 and March 2022 were retrospectively evaluated. Bronchoscopists assessed the cough severity upon completion of the procedure using a four-point cough scale. Cough severity was included as a predictive factor along with those reportedly involved in bronchoscopic diagnosis, and their impact on diagnostic yield was evaluated. Predictors of cough severity were also examined. A total of 275 patients were enrolled in this study. In the multivariate analysis, the diagnostic group (n = 213) had significantly more 'within' radial endobronchial ultrasound findings (odds ratio [OR] 5.900, p < 0.001), a lower cough score (cough score per point; OR 0.455, p < 0.001), and fewer bronchial generations to target lesion(s) (OR 0.686, p < 0.001) than the non-diagnostic group (n = 62). The predictive factors for severe cough include the absence of virtual bronchoscopic navigation (VBN) and prolonged examination time. Decreased cough severity was a positive predictive factor for successful EBUS-GS-TBB, which may be controlled using VBN and awareness of the procedural duration.

EBUS-TBLC increase the diagnosis rate in different type of peripheral pulmonary lesions

Background and objective: Recently, endobronchial ultrasonography with guide sheath-guided (EBUS-GS) has been increasingly used in the diagnosis of peripheral pulmonary lesions (PPLs) from human natural orifice. However, the diagnostic rate is still largely dependent on the location of the lesion and the probe. Here, we reported a new procedure to improve the diagnostic rate of EBUS-transbronchial lung cryobiopsy (EBUS-TBLC), which performed under general anesthesia with laryngeal mask airway (LMA) in all of the patients. This study retrospectively evaluated the diagnosis of PPLs with 'blind-ending' type (Type I) and 'pass-through' type procedures (Type II) of EBUS-GS-TBLB or EBUS-TBLC respectively. Methods: Retrospective review of 136 cases performed by EBUS-GS-TBLB or EBUS-TBLC for PPLs over 2 years. Results: A total of 126 cases EBUS-GS-TBLB or EBUS-TBLC were performed during the study period. Among them, 66 (52.4%) were performed Type I and 60 (47.6%) were performed Type II. Clinical baseline characteristics did not differ between two groups. The overall diagnosis rate of 126 patients with EBUS-GS-TBLB or EBUS-TBLC was 73% (92/126), and different method type have significant influence on the diagnostic yield (P = 0.012, x2 = 4.699). Among them, diagnostic yields for Type I with forceps biopsy (n=34), Type I with cryobiopsy (n=32), Type II with forceps biopsy (n=30), and Type II with cryobiopsy (n=30) were 72.5%, 64.5%, 70.4% and 74.2% respectively (Figure 2A). The study further compared the outcomes of different procedures in concentric and eccentric lesion. Diagnostic yields for Type I with eccentric (n=30), Type I with concentric (n=36), Type II with eccentric (n=34), and Type II with concentric (n=26) were 58.2%, 76.9%, 60.2% and 74.8%, respectively (P < 0.05). The incidence of complications in 126 patients was 2.6%. Conclusion: EBUS-GS-TBLB and EBUS-TBLC both are very safe and highly diagnostic technique; different method types have significant influence on the diagnostic yield. Moreover, Type II procedure has higher diagnostic yield. In addition, Type I with eccentric had the lowest diagnosis yield.

Transbronchial cryobiopsy using an ultrathin cryoprobe with a guide sheath for the diagnosis of pulmonary mucosa-associated lymphoid tissue lymphoma

Pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma is difficult to diagnose and relatively rare. Tissue sampling through transbronchial biopsy is often inadequate, necessitating surgical lung biopsy. However, a recently developed technique, transbronchial lung cryobiopsy (TBLC), has shown promise for obtaining larger specimens. A 1.1 mm cryoprobe has recently become available, and its usefulness has been increasingly reported. Use of a conventional cryoprobe for TBLC in diagnosing pulmonary MALT lymphoma has been previously reported; however, there are no reports on the use of a 1.1 mm ultrathin cryoprobe and guide sheath (GS). We aimed to assess the effectiveness and safety of using a 1.1 mm ultrathin cryoprobe in combination with a GS for diagnosing pulmonary MALT lymphoma using a simpler and safer method. We retrospectively analyzed the findings for four patients showing characteristic computed tomography (CT) findings of MALT lymphoma, including peripheral pulmonary lesions, air bronchogram nodules, and bronchiectasis, at our hospital. Each patient underwent endobronchial ultrasound (EBUS) with a GS, followed by TBLC using a 1.1 mm cryoprobe. Morphological diagnosis, immunohistochemical examination, and molecular testing were performed on the biopsy specimens to establish the diagnosis. Complications during the procedure were also monitored. We obtained 8-16 biopsy specimens in all four cases using a cryoprobe. Histopathological analysis of two cases revealed the infiltration of small lymphocytes with numerous lymphoepithelial lesions, confirming MALT lymphoma. Immunohistochemical examination further demonstrated B-cell lymphocyte proliferation and light-chain restriction, confirming monoclonality and providing a definitive diagnosis. In the remaining two cases, histopathological evidence of pulmonary MALT lymphoma was lacking. However, molecular testing using polymerase chain reaction to analyze immunoglobulin gene rearrangements revealed B-cell clonality, which supported the diagnosis. Molecular testing proved particularly useful when histopathological diagnosis alone was inconclusive. No complications such as pneumothorax or hemorrhage occurred during the procedure. The combination of a GS and EBUS facilitated specimen collection at the same location as EBUS, with the GS providing compression hemostasis and eliminating the need for an additional hemostatic device. Therefore, TBLC with a GS is a useful and safe method for diagnosing pulmonary MALT lymphomas and reproducibly yielded sufficient quantities of good-quality biopsy specimens.

Diagnostic value and safety of ultrathin bronchoscope and endobronchial ultrasonography with a guide sheath combined with rapid on-site evaluation system for peripheral pulmonary infectious diseases

BACKGROUND

The aim of this study was to investigate the diagnostic value and safety of ultrathin bronchoscope and endobronchial ultrasonography with a guide sheath (EBUS-GS) combined with rapid on-site evaluation (ROSE) system for peripheral pulmonary infectious diseases.

METHODS

The clinical data of 196 patients visiting our hospital, who had peripheral pulmonary lesions (PPLs) indicated by spiral computed tomography (CT) of the chest and were finally diagnosed as infectious PPLs, were retrospectively collected. Then the patients were divided into ultrathin bronchoscope + ROSE group, EBUS-GS + ROSE group and ultrathin bronchoscope + EBUS-GS + ROSE group based on different diagnostic techniques. Moreover, the general conditions, diagnostic results and specific operation parameters of the patients were recorded, and the diagnostic rate, sensitivity and complications were compared.

RESULTS

In ultrathin bronchoscope + EBUS-GS + ROSE group, the time of localizing lesions and operation time were the shortest, and the grade of bronchi reached by the bronchoscope was the highest. The differences were significant between any two groups (P<0.05). Patients with bacterial pneumonia, and patients with pulmonary tuberculosis and nontuberculous mycobacterial disease, ultrathin bronchoscope + EBUS-GS + ROSE group exhibited the highest definite diagnosis rate of bronchoscope and diagnostic sensitivity of ROSE system, with significant differences from those of the other two groups (P<0.05). The incidence rates of complications were low in all groups, and there were no significant differences between any two groups (P>0.05).

CONCLUSIONS

Ultrathin bronchoscope and EBUS-GS combined with ROSE system can prominently decrease the time of localizing lesions and operation time, remarkably improve the diagnostic accuracy and sensitivity and result in fewer complications.

Factors related to the diagnosis of lung cancer by transbronchial biopsy with endobronchial ultrasonography and a guide sheath

BACKGROUND

Transbronchial biopsy (TBB) with endobronchial ultrasonography and a guide sheath (EBUS-GS) is an effective examination tool for the diagnosis of lung cancer. Factors related to making the diagnosis are still not fully understood.

METHODS

A total of 367 patients who underwent EBUS-GS and were diagnosed with lung cancer in Saga University Hospital were investigated retrospectively. Clinical characteristics were compared between 244 patients who were diagnosed with lung cancer and 123 patients who were not diagnosed by TBB with EBUS-GS but were diagnosed by other examinations.

RESULTS

Size of target lesion, rate of patients with target lesion size ≥20 mm, presence of the bronchus sign, and detection by EBUS imaging were significantly associated with making the diagnosis (all p < 0.01). In patients whose lesion was detected by EBUS imaging, patients with positive findings within the lesion were significantly more often diagnosed by TBB with EBUS-GS than those with positive findings adjacent to the lesion (p < 0.01). The odds ratio (OR) of patients whose lesion was detected by EBUS imaging (OR [95% confidence interval] 14.5 [8.0-26.4]) tended to be higher compared to the ORs of size of lesion ≥20 mm (3.9 [2.2-6.8]) and the bronchus sign (7.5 [4.6-12.2]).

CONCLUSION

Targeted lesion diameter ≥20 mm, bronchus sign, and detection by EBUS imaging, especially within the lesion, are important factors for the diagnosis of lung cancer by TBB with EBUS-GS.

Advances in Diagnostic Bronchoscopy

The increase in incidental discovery of pulmonary nodules has led to more urgent requirement of tissue diagnosis. The peripheral pulmonary nodules are especially challenging for clinicians. There are various modalities for diagnosis and tissue sampling of pulmonary lesions, but most of these modalities have their own limitations. This has led to the development of many advanced technical modalities, which have empowered pulmonologists to reach the periphery of the lung safely and effectively. These techniques include thin/ultrathin bronchoscopes, radial probe endobronchial ultrasound (RP-EBUS), and navigation bronchoscopy—including virtual navigation bronchoscopy (VNB) and electromagnetic navigation bronchoscopy (ENB). Recently, newer technologies—including robotic-assisted bronchoscopy (RAB), cone-beam CT (CBCT), and augmented fluoroscopy (AF)—have been introduced to aid in the navigation to peripheral pulmonary nodules. Technological advances will also enable more precise tissue sampling of smaller peripheral lung nodules for local ablative and other therapies of peripheral lung cancers in the future. However, we still need to overcome the CT-to-body divergence, among other limitations. In this review, our aim is to summarize the recent advances in diagnostic bronchoscopy technology.

Endobronchial ultrasound-guided transbronchial biopsy with or without a guide sheath for peripheral pulmonary malignancy

Endobronchial ultrasound (EBUS)-guided transbronchial biopsy (TBB) is a common procedure used to diagnose peripheral pulmonary lesions (PPLs). However, existing literature did not conclusively show a difference in the ability of EBUS-TBB with and without a guide sheath (GS) to diagnose PPLs. This multicenter cohort study enrolled patients presenting for EBUS-TBB of PPLs that finally proved to be malignant. The diagnostic yield and complication rate were compared between patients undergoing EBUS-TBB with and without a GS (EBUS-TBB+GS versus EBUS-TBB-GS). A propensity score matching method was used to balance differences of pertinent clinical features between the two groups. The original cohort consisted of 975 patients (556 in EBUS-TBB-GS; 419 in EBUS-TBB+GS). GS guidance was more likely to be used with smaller (40 mm versus 44 mm) and middle or lower lobe (60% versus 35%) lesions. After propensity score matching, 720 (360 in each group) patients were included; the diagnostic yields for PPLs were 79% and 78% for EBUS-TBB-GS and EBUS-TBB+GS groups, respectively (p=0.649). The complication rates (5.8% versus 7.2% for bleeding; 0.6% versus 1.9% for pneumothorax) appeared to be lower in the EBUS-TBB+GS group, but the differences did not reach statistical significance. The procedure time was significantly longer in the EBUS-TBB+GS group than in the EBUS-TBB-GS group (29 min versus 24 min; p<0.001). In conclusion, adding a GS to EBUS-TBB did not improve the diagnostic yield for malignant PPLs. GS guidance was seemingly associated with a lower number of complications after TBB but contributed significantly to a longer procedure time.

Diagnostic value of radial endobronchial ultrasonographic features in predominant solid peripheral pulmonary lesions

Background

Transbronchial lung biopsy (TBLB) of peripheral pulmonary lesions (PPLs) is usually performed for a definite diagnosis. Radial probe endobronchial ultrasonography is often acknowledged as a good guidance method for TBLB as it can help physicians confirm the lesions’ position. It is also a non-invasive imaging diagnostic method. This clinical study was designed to evaluate the ability of radial endobronchial ultrasonography (R-EBUS) to differentiate benign from malignant predominant solid PPLs based on imaging features.

Methods

Patients with predominant solid PPLs were enrolled in this study retrospectively. TBLB was performed using R-EBUS with or without other guidance techniques. One typical sonographic image and one video of each lesion were recorded for analysis. Six radial probe endobronchial ultrasonographic image features (size, shape, echogenicity, margin, blood vessel, and linear-discrete air bronchogram) were studied by ultrasonography specialists and physicians who were blinded to the final diagnosis. The sum score model of the combined predictive factors indicated the best diagnostic accuracies for predicting malignant PPLs. The model group results were used to establish the diagnostic standard for a verification group.

Results

A total of 303 patients were enrolled in the model group from July 2018 to July 2019 at the Shanghai Chest Hospital (214 with malignant and 89 with benign lesions). The mean lesion long axis on computed tomographic images was 34.39±13.79 mm. There were significant statistical differences between benign and malignant lesions in the long axis, short axis, shape, margin, blood vessel, and linear-discrete air bronchogram assessed by radial endobronchial ultrasound. Long axis, lobulation, distinct but not sharp margin, absence of blood vessel, and absence of linear-discrete air bronchogram were good predictive factors of malignant lesions. A sum score model value of 79.54% of these combined factors indicated the best diagnostic accuracy for predicting malignant lesions. Eighty-seven patients were enrolled in the verification group from August to October 2019. The sum score model showed a diagnostic accuracy of 82.76%.

Conclusions

Radial endobronchial ultrasonographic features can differentiate malignant from benign lesions and thus have potential diagnosis value in predominant solid PPLs.

Analysis of risk factors for the development of a post-bronchoscopy respiratory infection in lung cancer patients

BACKGROUND

The development of pneumonia following bronchoscopy is a very important post-bronchoscopic complication, while lung abscesses after bronchoscopy are rare. However, bronchoscopic techniques have advanced, and recently, we have observed patients with lung abscess after bronchoscopy. Therefore, the risk factors might vary from those in past reports. This study was performed to identify the incidence of and risk factors for post-bronchoscopy respiratory infections.

METHODS

We retrospectively studied adult patients diagnosed with lung cancer by bronchoscopy at Fukujuji Hospital from January 2017 to June 2019. The infection and noninfection groups were compared. The incidence of lung abscess was compared between recent periods and 2013, when endobronchial ultrasonography with a guide sheath (EBUS-GS) was not yet used in our hospital.

RESULTS

We reviewed 327 patients, including 20 patients (6.1%) with infections. The risk factors for infection were necrosis and/or a cavity in the tumor (p < 0.001), a large tumor diameter (≥30 mm) (p = 0.010), and a low serum albumin level (<4.0 g/dL) (p = 0.010). We developed a predictive score with these risk factors, and the area under the curve was 0.737 (95% Cl: 0.610-0.864). No significant differences in age, current smoking status, or abnormal bronchoscopic findings were observed, although these were previously reported as risk factors. In total, 12 patients had lung abscesses (3.7%), which is a higher incidence than that in 2013 (0.8%).

CONCLUSIONS

The risk factors for developing post-bronchoscopy respiratory infection in our study varied from those in past reports, possibly because of the advancements in bronchoscopic techniques, such as EBUS-GS.

An update on the role of bronchoscopy in the diagnosis of pulmonary disease

Bronchoscopy has evolved over the past few decades and has been used by respiratory physicians to diagnose various airway and lung diseases. With the popularization of medical check-ups and growing interest in health, early diagnosis of lung diseases is essential. With the development of endobronchial ultrasound, ultrathin bronchoscopy, and electromagnetic navigational bronchoscopy, bronchoscopy has been able to widen its scope in diagnosing pulmonary diseases. In this review, we have described the brief history, role, and complications of bronchoscopy used in diagnosing pulmonary lesions, from simple flexible bronchoscopy to bronchoscopy combined with several up-to-date technologies.

Virtual bronchoscopic navigation without fluoroscopy guidance for peripheral pulmonary lesions in inexperienced pulmonologist

Objective

Fluoroscopy guidance is generally required for endobronchial ultrasonography with guide sheath (EBUS-GS) in peripheral pulmonary lesions (PPLs). Virtual bronchoscopic navigation (VBN) can guide the bronchoscope by creating virtual images of the bronchial route to the lesion. The diagnostic yield and safety profiles of VBN without fluoroscopy for PPLs have not been evaluated in inexperienced pulmonologist performing EBUS-GS.

Methods

Between January 2016 and June 2017, consecutive patients with PPLs referred for EBUS-GS at a single cancer center were enrolled. The diagnostic yield as well as safety profiles was retrospectively analyzed, and our preliminary experience was shared.

Results

A total of 109 patients with 109 lesions were included, 99 (90.8%) lesions were visible on EBUS imaging. According to the procedure time needed to locate the lesion on EBUS, 24.8% (27/109) were deemed technically difficult procedures; however, no significant relationships were identified between candidate parameters and technically difficult procedures. The overall diagnosis yield was 74.3% (81/109), and the diagnostic yield of malignancy was 83.7% (77/92). Lesions larger than 20 mm [odds ratio (OR), 2.758; 95% confidence interval (95% CI), 1.077-7.062; P=0.034] and probe of within type (OR, 3.174; 95% CI, 1.151-8.757, P=0.026) were independent factors leading to a better diagnostic yield in multivariate analysis. About 30 practice procedures were needed to achieve a stable diagnostic yield, and the proportion of technically difficult procedures decreased and stabilized after 70 practice procedures. Regarding complications, one patient (0.9%) had intraoperative hemorrhage (100 mL) which was managed under endoscopy.

Conclusions

VBN without fluoroscopy guidance is still useful and safe for PPLs diagnosis, especially for malignant diseases when performed by pulmonologist without previous experience of EBUS-GS. VBN may simplify the process of lesion positioning and further multi-center randomized studies are warranted.

Acute fibrinous and organizing pneumonia: two case reports and literature review

BACKGROUND

Acute fibrinous and organizing pneumonia (AFOP) is a very rare form of acute or subacute lung injury, which is characterized by patches of "fibrin balls" distributed within the alveoli. Given the lack of typical clinical manifestations, AFOP is often misdiagnosed as pneumonia, tuberculosis, etc. Definitive diagnosis is obtained from a lung biopsy. Corticosteroids are usually effective.

CASE PRESENTATION

We report two cases of patients with histopathological manifestations of AFOP, which were significantly improved after corticosteroid therapy. Previous reports of the clinical and pathological characteristics of AFOP were reviewed to improve clinicians' understanding of this disease.

CONCLUSIONS

Early identification and diagnosis are very important for AFOP treatment. The prognosis is acceptable after timely and effective treatment.

Chronic Pulmonary Melioidosis Masquerading as lung malignancy diagnosed by EBUS guided sheath technique

Diagnosis of pulmonary mass lesions can be challenging with several possible differentials. A 41-year-old Caucasian woman presented with intermittent non-specific chest pain on a background of 30 pack years of smoking history. A CT scan of the chest confirmed an opacity in the right lower lobe suspicious for primary pulmonary malignancy and PET scan showed moderate FDG avidity of the lesion. Conventional flexible bronchoscopy did not demonstrate an endobronchial lesion, Using Endobrochial Ultrasound (EBUS) Guide sheath technique, the lesion was localized in the posterior segment of the right lower lobe. Brushings, biopsies and washings were taken through the guide sheath, along with transbronchial cryobiopsy. Culture of bronchial brushings from the lesion on Ashdown's agar medium showed Burkholderia pseudomallei, confirming melioidosis. Treatment was with intravenous ceftazidime for 4 weeks, followed by oral sulphamethoxazole/trimethoprim for 3 months. During the follow up visits, the patient demonstrated significant improvement both clinically and radiologically.

Safety of diagnostic flexible bronchoscopy in patients with echocardiographic evidence of pulmonary hypertension

BACKGROUND

The presence of pulmonary hypertension (PH) and treatment with anticoagulant agents could potentially increase the risk for bleeding/hemodynamic complications associated with bronchoscopic procedures. The aim of this study was to assess the safety of diagnostic flexible bronchoscopy (FB) in patients with PH.

METHODS

A retrospective review of clinical records of patients with echocardiographic evidence of PH (right ventricular systolic pressure [RVSP] > 40 mm Hg) who underwent diagnostic FB between 2004 and 2016 at a single facility in Japan was conducted. Patients with no clinical evidence suggestive of PH who underwent FB during the same period were enrolled as a pairwise-matched control group; factors used in matching included age, sex, and performed procedures.

RESULTS

Overall, there were 45 patients in the PH group and 90 patients in the control group. Six (13%) patients in the PH group had severe PH (RVSP > 61 mm Hg). Forceps biopsies and transbronchial needle aspirations were performed in 62% and 13% of patients, respectively, in the PH group, and 58% and 13% of patients, respectively, in the control group. The total incidence of bleeding during FB was not significantly different between the two groups (18% versus 16%; p = 0.742). Vital signs recorded 2 h after FB were also not significantly different between the two groups. There were no episodes of cardiac arrhythmias or deaths associated with the FB procedures.

CONCLUSIONS

The data suggest that diagnostic FB procedures can be performed safely in patients with echocardiographic evidence of PH.

Endobronchial ultrasound: Echoing in the field of pediatrics

Endobronchial ultrasound (EBUS) is a useful technique for the diagnosis and staging of the lung and mediastinal lesions, which is crucial for selecting treatment protocol. Under EBUS guidance, transbronchial needle aspiration (TBNA) is widely applied for obtaining specimens for histological, cytological, and molecular evaluation. Recently, the EBUS scope designed for adults has been used in large pediatric candidates. The presence of lung masses and mediastinal lymphadenopathy in the pediatric population presents a diagnostic challenge; however, EBUS is a promising tool for pediatricians to address these challenging issues. In some centers, the adult EBUS echobronchoscope is applied in transesophageal procedures for pediatric patients. EBUS-guided TBNA can also be used to perform minimally invasive interventional therapy, such as fiducial marker placement for assisting precision radiation, brachytherapy, and radiofrequency ablation therapy. With the development of EBUS equipment designed specifically for children, pediatric EBUS will play an increasingly important role.