Feasibility and utility of transbronchial cryobiopsy in precision medicine for lung cancer: Prospective single-arm study

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.

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.

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.

Lung Involvement in Adult T-Cell Lymphoma Diagnosed Using Bronchoscopic Cryobiopsy: A Case Report and Review of the Literature

The diagnosis of pulmonary lymphoma using small tissue samples is difficult and often requires surgical procedures; thus, a less invasive sampling method is desirable. Moreover, pulmonary involvement in adult T-cell lymphoma (ATL) is often difficult to diagnose, especially in cases without characteristic flower cells. Here, we present the case of a 78-year-old man, in whom pathological examination of the transbronchial lung biopsy (TBLB) specimen did not reveal malignant findings; therefore, transbronchial lung cryobiopsy (TBLC) in combination with endobronchial ultrasonography (EBUS) was used to diagnose ATL based on the pathological findings. A literature review identified 18 cases of pulmonary lymphomas diagnosed using TBLC. Among the 19 cases, including our own, 16 cases were of B-cell lymphoma (84.2%), and the present case is the first case of ATL diagnosed using TBLC. Eighty percent of the cases underwent a biopsy (more than two samples) of the middle or lower lobe and were diagnosed without major complications. EBUS was used with TBLC in three cases to identify the location of the pulmonary lesions. In the present case, EBUS was also useful for avoiding vascular biopsy. Although large-scale prospective studies are required to establish precise guidelines for diagnosing pulmonary lymphomas using TBLC, our case report and review contributes to a deeper understanding of the diagnosis of rare diseases.

Suitability of respiratory endoscopy for sampling malignant thoracic tumors for comprehensive genomic profiling

Comprehensive genomic profiling (CGP) is implemented to detect actionable gene aberrations and design matched therapies. Although malignant thoracic tumors are commonly detected through respiratory endoscopy, it is questionable whether the small specimens obtained thereof are sufficient for CGP. Therefore, this study aimed to investigate the suitability of respiratory endoscopy for sampling primary and metastatic thoracic tumors for CGP. Patients whose specimens were collected through respiratory endoscopy and assessed by pathologists to determine their suitability for CGP at our institution between June 2019 and May 2022 were reviewed retrospectively. The suitability of each procedure as a sampling technique for CGP and, in the cases actually analyzed, the distribution of the detected gene aberration were assessed. In total, 122 patients were eligible for analysis; the median age was 61 (range, 29-86) years, and 71 (58.2%) patients were male. Primary intrathoracic tumors were found in 91 (74.6%) cases, including 84 (68.9%) primary lung cancers; the remaining thoracic metastases of extrathoracic origin included various types. The suitability rates of specimens obtained using conventional bronchoscopy with and without cryobiopsy, endobronchial ultrasound-guided transbronchial needle aspiration, and medical thoracoscopy were 82.8% (24/29), 70.4% (19/27), 72.9% (35/48), and 100% (18/18), respectively. Of the 96 cases judged suitable, 83 were subjected to CGP, and all but one were successfully analyzed. Finally, 47 (56.6%) patients had at least one actionable gene aberration and eight (9.6%) were treated with the corresponding targeted therapies. In conclusion, specimens obtained through respiratory endoscopy are suitable for CGP; medical thoracoscopy and cryobiopsy in conventional bronchoscopy are particularly useful.

Transbronchial lung cryobiopsy for peripheral pulmonary lesions. A narrative review

An increasing number of peripheral pulmonary lesions (PPLs) requiring tissue verification to establish a definite diagnosis for further individualized management are detected due to the growing adoption of lung cancer screening by chest computed tomography (CT), especially low-dose CT. However, the morphological diagnosis of PPLs remains challenging. Transbronchial lung cryobiopsy (TBLC) that can retrieve larger specimens with more preserved cellular architecture and fewer crush artifacts in comparison with conventional transbronchial forceps biopsy (TBFB), as an emerging technology for diagnosing PPLs, has been demonstrated to have the potential to resolve the clinical dilemma pertaining to currently available sampling devices (e.g., forceps, needle and brush) and become a diagnostic cornerstone for PPLs. Of note, with the introduction of the 1.1 mm cryoprobe that will be more compatible with advanced bronchoscopic navigation techniques, such as radial endobronchial ultrasound (r-EBUS), virtual bronchoscopic navigation (VBN) and electromagnetic navigation bronchoscopy (ENB), the use of TBLC is expected to gain more popularity in the diagnosis of PPLs. While much remains for exploration using the TBLC technique for diagnosing PPLs, it can be envisaged that the emergence of additional studies with larger data accrual will hopefully add to the body of evidence in this field.

Clinical outcomes of transbronchial cryobiopsy using a 1.1-mm diameter cryoprobe for peripheral lung lesions - A prospective pilot study

OBJECTIVES

Transbronchial cryobiopsy (TBCB) is a novel technique for the diagnosis of peripheral lung lesions (PLLs). We aim to evaluate the clinical outcomes of TBCB using a new 1.1-mm diameter cryoprobe for the diagnosis of PLLs.

MATERIALS AND METHODS

We performed a prospective observational pilot study on the diagnosis of PLLs (diameter ≤30 mm) by TBCB, using a 1.1-mm diameter cryoprobe with radial endobronchial ultrasound (RP-EBUS), virtual bronchoscopic navigation and fluoroscopy from December 2021 to July 2022. Primary outcome was the pathological diagnostic yield of TBCB, and secondary outcome was adverse event.

RESULTS

A total of 50 patients were enrolled (mean lesion size, 21 mm). TBCB was performed in 49 patients up to three times except for the one with "invisible" finding on RP-EBUS. The overall diagnostic yield of TBCB was 90% (45/50). There was no difference in the diagnostic yield between size (20 mm vs. 20-30 mm; 88% [22/25] vs. 92% [23/25]; P = 1.000), RP-EBUS findings (concentric vs. others; 97% [28/29] vs. 81% [17/21]; P = 0.148), and acute angle location (apical segment of both upper lobes vs. others; 92% [12/13] vs. 89% [33/37]; P = 1.000). The cumulative diagnostic yields of the first, second, and third TBCB were 82% (41/50), 88% (44/50), and 90% (45/50), respectively. Mild bleeding was developed in 56% (28/50), and moderate bleeding was found in 26% (13/50).

CONCLUSION

TBCB using a 1.1-mm diameter cryoprobe is an effective, reasonable method for the diagnosis of PLLs regardless of its size, RP-EBUS finding, and anatomical location without serious complication.

TRIAL REGISTRATION

Clinical Trials.Gov (NCT05046093).

Invasive Diagnostic Procedures from Bronchoscopy to Surgical Biopsy-Optimization of Non-Small Cell Lung Cancer Samples for Molecular Testing

Background and Objectives: Treatment of advanced lung cancer (LC) has become increasingly personalized over the past decade due to an improved understanding of tumor molecular biology and antitumor immunity. The main task of a pulmonologist oncologist is to establish a tumor diagnosis and, ideally, to confirm the stage of the disease with the least invasive technique possible. Materials and Methods: The paper will summarize published reviews and original papers, as well as published clinical studies and case reports, which studied the role and compared the methods of invasive pulmonology diagnostics to obtain adequate tumor tissue samples for molecular analysis, thereby determining the most effective molecular treatments. Results: Bronchoscopy is often recommended as the initial diagnostic procedure for LC. If the tumor is endoscopically visible, the biopsy sample is susceptible to molecular testing, the same as tumor tissue samples obtained from surgical resection and mediastinoscopy. The use of new sampling methods, such as cryobiopsy for peripheral tumor lesions or cytoblock obtained by ultrasound-guided transbronchial needle aspiration (TBNA), enables obtaining adequate small biopsies and cytological samples for molecular testing, which have until recently been considered unsuitable for this type of analysis. During LC patients' treatment, resistance occurs due to changes in the mutational tumor status or pathohistological tumor type. Therefore, the repeated taking of liquid biopsies for molecular analysis or rebiopsy of tumor tissue for new pathohistological and molecular profiling has recently been mandated. Conclusions: In thoracic oncology, preference should be given to the least invasive diagnostic procedure providing a sample for histology rather than for cytology. However, there is increasing evidence that, when properly processed, cytology samples can be sufficient for both the cancer diagnosis and molecular analyses. A good knowledge of diagnostic procedures is essential for LC diagnosing and treatment in the personalized therapy era.

Radial Endobronchial Ultrasound-guided Transbronchial Cryobiopsy versus Forceps Biopsy for the Diagnosis of Solitary Pulmonary Nodules: A Prospective Randomised Trial

Background

Improvements in pulmonary diagnostic imaging and the development of lung cancer screening are increasing the prevalence of Solitary pulmonary nodules (SPNs). Fluoroscopically guided radial endobronchial ultrasound (EBUS) with transbronchial forceps biopsy (TB-FB) has been the conventional diagnostic method. Transbronchial cryobiopsy (TB-CB) is an alternative biopsy method. We sought to compare transbronchial cryobiopsy to transbronchial forceps biopsy for the diagnosis of SPNs.

Methods

A prospective, single-centre, randomised controlled trial was conducted at the Royal Adelaide Hospital (RAH). Patients with SPNs were randomised to either 5 transbronchial forceps biopsies or one transbronchial cryobiopsy. Complete blinding of investigators and participants was not possible, as transbronchial cryobiopsy required general anaesthesia. The primary outcome was diagnostic yield with secondary outcomes of specimen size, diagnostic yield for subsets challenging to access with forceps and safety.

Results

The overall diagnostic yield for the 28 enrolled subjects was 76.8%(22/28). The diagnostic yield was 91.7% (11/12 patients) for transbronchial cryobiopsy and 68.8% (11/16 patients) for forceps biopsy (p=0.14). Median biopsy sizes were consistently larger for the cryobiopsy arm at 7.0mm compared to 2.5mm(p<0.0001). An eccentric EBUS image signalling the probe was adjacent to the nodule occurred in 4/28 cases, and TB-CB confirmed a diagnosis in 3/3 randomised to this arm. There were no major complications with either technique.

Conclusion

Transbronchial cryobiopsy under the guidance of fluoroscopy and radial EBUS facilitates larger biopsy specimens without a significant increase in major complications. Further research is required to confirm the effect on diagnostic yield; however, our study supports a role for TB-CB in the diagnosis of SPNs and small, nodule-adjacent biopsies.

Clinical Trial Registration Number

Reference number of R20160213(HREC/16/RAH/37).

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.

Diagnostic efficacy of cryobiopsy for peripheral pulmonary lesions: A propensity score analysis

OBJECTIVES

Recently introduced cryobiopsy can provide quantitatively and qualitatively excellent specimens. However, few studies have directly compared the diagnostic yield of cryobiopsy for peripheral pulmonary lesions (PPLs) with that of conventional sampling methods.

MATERIAL AND METHODS

We retrospectively reviewed data from consecutive patients who underwent diagnostic bronchoscopy using radial endobronchial ultrasound and virtual bronchoscopic navigation for PPLs (October 2015 to September 2020). Patients who underwent cryobiopsy were assigned to the cryo group, whereas those who did not undergo cryobiopsy were assigned to the conventional group. The diagnostic outcomes of both groups were compared using propensity score analyses.

RESULTS

A total of 2,724 cases were identified, including 492 and 2,232 cases in the cryo and conventional groups, respectively. Propensity scoring was performed to match baseline characteristics, and 481 pairs of cases were selected for each matched group (m-group). The diagnostic yield was significantly higher in the m-cryo group than in the m-conventional group (89.2% vs. 77.6%, odds ratio [OR] = 2.36 [95% confidence interval [CI] = 1.65-3.38], P < 0.001). Propensity score stratification (OR = 2.35 [95% CI = 1.71-3.23]) and regression adjustment (OR = 2.54 [95% CI = 1.83-3.52]) also demonstrated the diagnostic advantages of cryobiopsy. The subgroup analysis revealed that cryobiopsy was notably effective for lesions in the middle lobe/lingula, right/left lower lobe, lesions with ground-glass opacity, and lesions invisible on chest radiography. Although there were more cases of grade 2 and 3 bleeding in the m-cryo group than in the m-conventional group (38.0% vs. 10.2% and 1.5% vs. 0.8%, respectively; P < 0.001), no grade 4 bleeding was observed.

CONCLUSION

The propensity score analyses revealed that cryobiopsy was associated with a higher diagnostic yield for PPLs than conventional sampling methods. However, increased bleeding risk should be noted as a potential complication.

[Complicated hematomediastinum in a 76-year-old patient after performing an endosonographically guided transbronchial cryobiopsy (EBUS-TBCB) with suspected lymphoma]

We present the case of a patient with severe complications from mediastinal bleeding after endosonographically guided transbronchial cryobiopsy (EBUS-TBKB) with suspected advanced lymphoma. The EBUS-TBKB is a new effective examination method in interventional pneumology for the diagnosis of diseases with mediastinal lymph node enlargement and intrathoracic tumors, with which large tissue cylinders in the mediastinum can be obtained. Due to the high diagnostic value of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for the clarification of lymphadenopathy, the examination should not be carried out as a routine application. Indications for a primary EBUS-TBKB arise when there is a suspicion of intrathoracic malignant lymphomas or other rare tumors in which extensive unfragmented tissue material is required for diagnosis. A rare complication that has not yet been described in the literature is a hematomediastinum, so that a careful risk assessment of possible bleeding complications should be carried out before intervention and the more invasive mediastinoscopy can be a safer examination method.

The first case report of Paragonimus westermani infection diagnosed by transbronchial lung cryobiopsy

We report a case of pulmonary paragonimiasis diagnosed by transbronchial lung cryobiopsy (TBLC). TBLC is likely to be a superior method to transbronchial forceps biopsy because TBLC can get larger specimens, resulting in a higher chance of containing the eggs. A male patient aged 57 years presented with hemoptysis and dyspnea on exertion. His initial chest computed tomography scans showed a cavitary nodule with a peripheral ground-glass appearance, leading to a prescription of an oral antibiotic, with an initial assumption of pneumonia. A follow-up chest computed tomography, however, revealed an appearance of a new nodule adjacent to the original nodule. TBLC and transbronchial forceps biopsy were done to rule out lung cancer and eventually, the eggs of Paragonimus westermani were found using TBLC. Praziquantel was prescribed, showing improvements in symptoms and chest X-ray findings. TBLC has more potential to be utilized as a diagnostic method than transbronchial forceps biopsy because it has a better chance to confirm pulmonary paragonimiasis, which can be initially suspected as pulmonary tuberculosis or lung cancer.

Thoracic SMARCA4-deficient undifferentiated tumor diagnosed by transbronchial mediastinal cryobiopsy: A case report

Thoracic SMARCA4-deficient undifferentiated tumors (SMARCA4-UT) have a poor prognosis and are often diagnosed at an inoperable advanced stage. Herein, we report a case of SMARCA4-UT diagnosed by endobronchial ultrasound-guided transbronchial cryobiopsy (EBUS-cryo). The patient was a 42-year-old man with a history of smoking. Chest computed tomography revealed a right upper lobe nodule and an enlarged #11s lymph node. Core tissues could not be obtained by EBUS-guided transbronchial needle aspiration (EBUS-TBNA) for diagnosis and mediastinal staging; hence, EBUS-guided intranodal forceps biopsy (EBUS-IFB) was performed. However, a detailed diagnosis beyond poorly differentiated carcinoma could not be obtained. Subsequent EBUS-cryo provided sufficient specimens for immunohistochemical and molecular evaluation and SMARCA4-UT was definitively diagnosed. Thus, EBUS-cryo could be of additional diagnostic value for uncommon tumors, such as SMARCA4-UT, conjointly with EBUS-IFB as well as EBUS-TBNA.

Efficacy of combined transbronchial lung cryobiopsy and conventional forceps biopsy for lung malignancies: a prospective cohort study

There are few prospective reports of transbronchial lung cryobiopsy (TBLC) for malignant tumors in combination with forceps biopsy. We investigated the clinical parameters in which TBLC is superior to forceps biopsy. This is a prospective cohort study to analyse the efficacy of TBLC for suspected malignancy. TBLC was performed after brushing cytology and forceps biopsy, and the diagnostic yield for TBLC, brushing cytology, and forceps biopsy were examined. Adverse events were defined as those requiring additional procedures. Next-generation sequencing (NGS) analysis was performed in each case of non-small cell lung cancer. Of the 100 patients, malignancy was confirmed in 94 cases. The diagnostic yield for TBLC/forceps biopsy/brushing cytology was 86/81/82% respectively, while the diagnostic yield for all procedures combined was 94%. There was no significant difference in the diagnostic yield between TBLC and forceps biopsy. When comparing the biopsy site, the diagnostic yield for TBLC at the lower lobe was significantly higher than forceps biopsy (P < 0.01). Endobronchial ultrasonography imaging using a guide-sheath did not significantly differ in the diagnostic yield of TBLC. The success rate of NGS for TBLC specimens was 100% (26 cases). Adverse events included two cases of severe bleeding. TBLC of peripheral lesions may improve the diagnostic yield when combined with forceps biopsy and brushing cytology. The diagnostic yield of TBLC was higher at the lower lobes. Furthermore, TBLC provided sufficient specimen quality for NGS.

Suitability of transbronchial needle aspiration for genotyping peripheral pulmonary tumors

Background

Transbronchial needle aspiration (TBNA) is a sampling tool that has demonstrated a higher accuracy in the diagnosis of peripheral pulmonary lesions (PPL) compared to other techniques. However, there are no studies investigating the value of TBNA in defining the genotype of peripheral lung cancer.

Objective

To evaluate the accuracy of TBNA in defining the molecular characteristics of peripheral lung cancer.

Methods

Consecutive patients who underwent TBNA for the diagnosis of a PPL at the Pulmonary Unit of the Azienda Ospedali Riuniti of Ancona (Italy) between January 2020 and September 2022 were included in the study. TBNA was performed under fluoroscopic guidance and the additional support of an ultrasound miniprobe, with an ultrathin bronchoscope with a flexible 21G needle. Samples were smeared on glass slides for cytological evaluation and flushed in 10% neutral-buffered formalin for cell-blocks.

Results

154 patients were enrolled:55 were diagnosed with adenocarcinoma and 21 with squamous cell carcinoma. TBNA correctly diagnosed 43/55 (78.2%) patients with adenocarcinoma and 17/21 (81.0%) patients with squamous cell carcinoma, with a sensitivity of 77.5%. Complete genotyping for guiding targeted therapies was obtained in 52 patients (86.6%).

Conclusions

TBNA is a valid tool for the diagnosis of PPL, allowing a correct diagnosis and a complete genotyping of the tumors in a considerable proportion of patients.

Efficacy of Radial Endobronchial Ultrasound (R-EBUS) guided transbronchial cryobiopsy for peripheral pulmonary lesions (PPL...s): A systematic review and meta-analysis

BACKGROUND

Transbronchial lung cryobiopsy (TBLC) is frequently described for the diagnosis of diffuse parenchymal lung diseases (DPLD). A few studies have reported transbronchial cryobiopsy for the diagnosis of peripheral pulmonary lesions (PPL...s). We aimed to study the utility and safety of transbronchial cryobiopsy for the diagnosis of PPL...s.

METHODS

We performed a systematic search of the PubMed and Embase databases to extract the relevant studies. We then performed a meta-analysis to calculate the diagnostic yields of transbronchial cryobiopsy and bronchoscopic forceps biopsy.

RESULTS

Following a systematic search, we identified nine relevant studies (300 patients undergoing cryobiopsy). All used Radial Endobronchial Ultrasound (R-EBUS) for PPL localization. The pooled diagnostic yield of transbronchial cryobiopsy was 77% (95% CI, 71%...84%) (I^2=38.72%, p=0.11). The diagnostic yield of forceps biopsy was 72% (95% CI, 60%...83%) (I^2=78.56%, p<0.01). The diagnostic yield of cryobiopsy and forceps biopsy was similar (RR 1.05, 95% CI 0.96...1.15), with a 5% risk difference for diagnostic yield (95% CI, ...6% to 15%). There was significant heterogeneity (I^2=57.2%, p=0.017), and no significant publication bias. One severe bleeding and three pneumothoraxes requiring intercostal drain (ICD) placement (major complication rate 4/122, 1.8%) were reported with transbronchial cryobiopsy.

CONCLUSIONS

R-EBUS guided transbronchial cryobiopsy is a safe and efficacious modality. The diagnostic yields of TBLC and forceps biopsy are similar. More extensive multicentre randomized trials are required for the further evaluation and standardization of transbronchial cryobiopsy for PPL...s.

Proposal of a novel pipeline involving precise bronchoscopy of distal peripheral pulmonary lesions for genetic testing

Next-generation sequencing (NGS) has become increasingly more important for lung cancer management. We now expect biopsies to be sensitive, safe, and yielding sufficient samples for NGS. In this study, we propose ultraselective biopsy (USB) with sample volume adjustment (SVA) as a novel method that integrates an ultrathin bronchoscope, radial probe endobronchial ultrasound, and the direct oblique method for ultraselective navigation, and adjustment of sample volume for NGS. Our purpose was to estimate the diagnostic potential and the applicability of USB-SVA for amplicon-based NGS analysis. The diagnostic yield of bronchoscopy in forty-nine patients with malignant peripheral pulmonary lesions (PPLs) was retrospectively analyzed, and amplicon-based NGS analysis was performed on samples from some patients using USB. The diagnostic yields of distal PPLs in the USB group were significantly higher than those in the non-USB group (90.5% vs. 50%, respectively, p = 0.015). The extracted amounts of nucleic acids were at least five times the minimum requirement and the sequence quality met the criteria for the Oncomine™ Target Test. Only the tumor cell content of some samples was insufficient. The feasibility of the pipeline for USB, SVA, and amplicon-based NGS in distal PPLs was demonstrated.

Comparison of next-generation sequencing and cobas EGFR mutation test v2 in detecting EGFR mutations

BACKGROUND

As the number of genetic mutations that must be tested increases, the Oncomine Dx Target test (ODxTT), which can simultaneously detect multiple cancer-related genes is becoming the main test used in preference to single-molecule testing. In this study, we evaluated the performance of ODxTT and cobas EGFR mutation test v2 (cobas EGFR), one of the single-molecule tests, in detecting EGFR mutations.

METHODS

Samples from 211 patients diagnosed with NS-NSCLC were tested simultaneously or sequentially with the cobas EGFR mutation test and ODxTT. We compared the success and detection rates of both tests and evaluated their equivalence by determining the concordance rate and k-coefficient of both tests.

RESULTS

The success rate in detecting EGFR mutations was 95.7% for ODxTT and 100% for cobas EGFR. EGFR mutations were detected in 26.5% of samples with ODxTT and in 28.0% with cobas EGFR. For the 200 samples successfully analyzed with both tests, the concordance rate and k-coefficient were 97.5% and 0.938, respectively. ODxTT failed to detect two exon 19 deletion mutations (p.E746_P753delinsVS and p.E746_P753delinsLS), and cobas EGFR failed to detect three instances of an exon 19 deletion (p.L747_P753delinsS), L861R, and an exon 20 insertion.

DISCUSSION

The success rate of ODxTT is slightly inferior to that of cobas EGFR. ODxTT shared a high concordance rate and k-coefficient with cobas EGFR in detecting EGFR mutations, but discordant results between the two tests were observed in a few cases, mainly due to the difference of detectable EGFR variants.

Esophageal submucosal tumor diagnosed with EBUS-guided transbronchial mediastinal cryobiopsy: A case report

Cryobiopsy is advantageous for collecting larger specimens with minimum crushing compared to forceps biopsy and transbronchial needle aspiration (TBNA), but it has not been widely used for mediastinal tumors. In this report, a leiomyoma of the thoracic esophagus was diagnosed with endobronchial ultrasound-guided transbronchial mediastinal cryobiopsy (EBUS-cryo). An asymptomatic 49-year-old woman had a 2.6-cm sized submucosal tumor (SMT) of the esophagus adjacent to the trachea and left main bronchus. EBUS-TBNA and EBUS-guided intranodal forceps biopsy were performed, followed by EBUS-cryo. The biopsy forceps could not be inserted into the tumor, but the cryoprobe was smoothly inserted. EBUS-TBNA could not obtain enough spindle-shaped tumor cells for immunohistochemical staining, but EBUS-cryo provided sufficient specimens for diagnosing the leiomyoma. Adding EBUS-cryo to EBUS-TBNA has recently been reported to achieve high diagnostic yields for lymphomas, uncommon tumors, and benign diseases. EBUS-cryo seems a valid diagnostic option for esophageal SMTs that are difficult to diagnose with needles and forceps.

Clinical Utility of Rapid On-Site Evaluation of Touch Imprint Cytology during Cryobiopsy for Peripheral Pulmonary Lesions

Simple Summary

With increasing interest in precision medicine for lung cancer, cryobiopsy is expected to improve the success rate not only for histological diagnosis, but also for next-generation sequencing. Rapid on-site evaluation (ROSE) is an immediate cytological evaluation performed during bronchoscopy. However, little is known about its clinical utility during cryobiopsy. We retrospectively reviewed the data of 63 consecutive patients who underwent cryobiopsy with ROSE of touch imprint cytology (ROSE-TIC) for solid peripheral pulmonary lesions. When the results of ROSE-TIC of each patient were compared directly with the histological findings of the corresponding specimen, the sensitivity, specificity, and positive and negative predictive values were 69.8%, 90.0%, 93.8%, and 58.1%, respectively. The concordance rate was 76.2%. Therefore, we believe that ROSE-TIC, due to its high specificity and positive predictive value, may be a potential tool in deciding whether cryobiopsy sampling could be finished during bronchoscopy.

Abstract

Cryobiopsy enables us to obtain larger specimens than conventional forceps biopsy despite the caution regarding complications. This study aimed to evaluate the clinical utility of rapid on-site evaluation of touch imprint cytology (ROSE-TIC) during cryobiopsy of peripheral pulmonary lesions (PPLs). We retrospectively reviewed the data of consecutive patients who underwent cryobiopsy for solid PPLs between June 2020 and December 2021. ROSE-TIC was performed on the first specimen obtained via cryobiopsy and assessed using Diff-Quik staining. The results of ROSE-TIC for each patient were compared with the histological findings of the first cryobiopsy specimen. Sixty-three patients were enrolled in this study. Overall, 57 (90.5%) lesions were ≤30 mm in size and 37 (58.7%) had positive bronchus signs. The radial endobronchial ultrasound findings were located within and adjacent to the lesion in 46.0% and 54.0% of the cases, respectively. The sensitivity, specificity, and positive and negative predictive values of the ROSE results for histological findings of the corresponding specimens were 69.8%, 90.0%, 93.8%, and 58.1%, respectively. The concordance rate was 76.2%. In conclusion, ROSE-TIC, due to its high specificity and positive predictive value, may be a potential tool in deciding whether cryobiopsy sampling could be finished during bronchoscopy.

Applications of cryobiopsy in airway, pleural, and parenchymal disease

INTRODUCTION

:Cryobiopsy is a novel diagnostic technique for thoracic diseases which has been extensively investigated over the past 20 years. It was originally proposed for the diagnosis of endobronchial lesions and diffuse parenchymal lung disease due to limitations of conventional sampling techniques including small size and presence of artifacts.

AREAS COVERED

:We will review recent evidence related to the expanding use of cryobiopsy in thoracic diseases. To identify references, the MEDLINE database was searched from database inception until May 2022 for case series, cohort studies, randomized controlled trials, systematic reviews and meta-analyses related to cryobiopsy.

EXPERT OPINION

Cryobiopsy has expanding applications in the field of thoracic diseases. Evidence to support transbronchial cryobiopsy as an alternative to surgical lung biopsy is increasing and was recently endorsed as a conditional recommendation by the latest American Thoracic Society guideline update for Idiopathic Pulmonary Fibrosis. Developments in technology and technique, in particular the availability of a 1.1 mm flexible cryoprobe, have extended applications to pulmonary diseases, including diagnosis of interstitial lung diseases, peripheral pulmonary lesions, and lung transplant rejection.

A Prospective Validation Study of Lung Cancer Gene Panel Testing Using Cytological Specimens

Simple Summary

The gold standard for genetic panel test samples is considered to be tissue specimens. However, in clinical practice, tissue specimens are often unavailable. Therefore, using an amplicon-based high-sensitivity next-generation sequencing panel test capable of measuring eight druggable genes, we enrolled patients who underwent diagnostic procedures to evaluate analysis accuracy, nucleic acid yield, and quality using cytological specimens. Cytological specimens were suitable for both nucleic acid yield and specimen quality due to the ease of collection and processing. Cytological sample analysis detected gene mutations in 68.7% of lung adenocarcinomas, and these samples were consistent with companion diagnostic tests 99.5% of the time. Moreover, the allele frequency of gene mutations in cytological specimens showed a high correlation with tissue specimens. This is the first study to prospectively evaluate the feasibility of a lung cancer gene panel test using cytological specimens.

Abstract

Background: Genetic panel tests require sufficient tissue samples, and therefore, cannot always be performed. Although collecting cytological specimens is easier than tissue collection, there are no validation studies on the diagnostic accuracy of lung cancer gene panel tests using cytology samples. Methods: Using an amplicon-based high-sensitivity next-generation sequencing panel test capable of measuring eight druggable genes, we prospectively enrolled consecutive patients who underwent diagnostic procedures. We evaluated the analysis accuracy rate, nucleic acid yield, and the quality of cytological specimens under brushing, needle aspiration, and pleural effusion. We then compared these specimens with collected tissue samples. Results: In 163 prospectively enrolled cases, nucleic acid extraction and analysis accuracy was 100% in cases diagnosed with adenocarcinoma. Gene mutations were found in 68.7% of cases with 99.5% (95% CI: 98.2–99.9) concordance to companion diagnostics. The median DNA/RNA yield and DNA/RNA integrity number were 475/321 ng and 7.9/5.7, respectively. The correlation coefficient of the gene allele ratio in 64 cases compared with tissue samples was 0.711. Conclusion: The success of gene analysis using cytological specimens was high, and the yield and quality of the extracted nucleic acid were sufficient for panel analysis. Moreover, the allele frequency of gene mutations in cytological specimens showed high correlations with tissue specimens.

Pathological criteria for multiplex gene-panel testing using next-generation sequencing in non-small cell lung cancer

BACKGROUND

Multiplex gene-panel tests have recently been developed, including the Oncomine Dx Target Test multi-CDx system (ODxTT), and are commonly used to determine the adaptation of molecular-targeting drugs in non-small cell lung cancer. However, in actual clinical settings, we obtain false results owing to the small biopsy samples. We aimed to optimize tissue preparation methods to improve the success rate.

PATIENTS AND METHODS

We investigated 88 biopsy samples. The area and nucleated cell count in the first cut section were quantified using a morphometric software. Pathological parameters, including "total tissue area" and "total nucleated cell count," were calculated by multiplying the total number of slides submitted to ODxTT. Optimal cutoff values to obtain the best success rate were also determined. Additionally, we morphometrically measured actual tumor cell proportions and attempted to determine the lower limit possible to detect mutations.

RESULTS

Optimal cutoff values for "total nucleated cell count" and "total tissue area" were 132,885 and 32.94 mm², respectively. The actual tumor cell proportions ranged from 4.6 to 97.7%. Even in cases with actual tumor cell proportions of less than 20% (ranging from 4.6 to 19.7%), there was no false negative.

CONCLUSION

Thus, we proposed the pathological criteria for accurate ODxTT. Our result suggested that tumor cell proportions of less than 20% (around 5%) could be applicable for ODxTT. We hope that our results will help pathologists to choose between the multi-plex test (ODxTT) or single-plex test in routine diagnostics.

Comparison of the analytical performance of the Oncomine dx target test focusing on bronchoscopic biopsy forceps size in non-small cell lung cancer

BACKGROUND

Next-generation sequencing (NGS) has been implemented in clinical oncology to analyze multiple genes and to guide targeted therapy. Although the pathological diagnosis and biomarker tests for patients with advanced lung cancer have mostly been obtained with small biopsy samples, especially with bronchoscopic approaches, the performance for NGS with respect to the different sizes of biopsy forceps remains little known.

METHODS

We retrospectively reviewed consecutive patients with non-small cell lung cancer, whose FFPE samples were obtained by endobronchial biopsy/transbronchial biopsy and were submitted for the Oncomine Dx Target Test (ODxTT). We compared the analytical performance for ODxTT with respect to the size of biopsy forceps.

RESULTS

A total of 103 samples were identified. The success rate of the ODxTT for the group with all samples obtained with small forceps biopsies (70%) was lower than that of the group with some or all samples obtained with standard forceps biopsies (83%), although without a statistically significant difference (p = 0.20). With regard to the reason for unsuccessful analysis, the proportion of the samples which did not pass the nucleic acid concentration threshold in the former group (15%) was higher compared with that of the latter group (4%) (p = 0.08). The proportion of tissue size 4 mm² or larger in the former group (70%) was lower than that in the latter group (93%) (p = 0.01).

CONCLUSION

The analysis of ODxTT for specimens biopsied using only small forceps is prone to be unsuccessful due to an insufficient amount of nucleic acid.

Diagnostic Yield of Transbronchial Cryobiopsy Guided by Radial Endobronchial Ultrasound and Fluoroscopy in the Radiologically Suspected Lung Cancer: A Single Institution Prospective Study

Transbronchial cryobiopsy (TBCB) is being studied in the diagnosis of peripheral lung lesions; however, there are only a few clinical studies around the world. The aim of our study was to evaluate the diagnostic values and safety of transbronchial cryobiopsy for radiologically suspected peripheral lung cancer. The prospective clinical study was executed from September 2019 to September 2021 at a tertiary clinical centre in Lithuania. A total of 48 patients out of 102 underwent combined procedures of transbronchial forceps biopsy (TBFB) and TBCB. Diagnostic values and safety outcomes of TBFB and TBCB were analysed. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were 72.9%, 100%, 100%, 7.7%, and 88.0% for TBFB, 85.1%, 100%, 100%, 12.5%, and 93% for TBCB, as well as 91.5%, 100%, 100%, 20.0% and 96.7% for the combined procedures, respectively, with a significantly higher accuracy for cryobiopsies compared to forceps biopsies (p < 0.05). The diagnostic values for transbronchial cryobiopsies were similar, irrespective of the radial mini probe endobronchial ultrasound (RP-EBUS) position, lesion size or bronchus sign, however, the sensitivity of the combined procedures in cases with RP-EBUS adjacent to the target was significantly higher compared to TBFB (86.2% vs. 64.3%, p = 0.016). Samples of cryobiopsies were significantly larger than forceps biopsies (34.62 mm2 vs. 4.4 mm2, p = 0.001). The cumulative diagnostic yield of transbronchial cryobiopsy was 80.0% after the second biopsy and reached a plateau of 84.1% after four biopsies. No severe bleeding, pneumothorax, respiratory failure or death was registered in our study. TBCB is a potentially safe procedure, which increases diagnostic values in diagnosing peripheral lung lesions compared to TBFB.

Efficacy and Safety of Cryobiopsy vs. Forceps Biopsy for Interstitial Lung Diseases, Lung Tumors, and Peripheral Pulmonary Lesions: An Updated Systematic Review and Meta-Analysis

Background

Cryobiopsy has emerged as a novel alternative to conventional forceps biopsy for the diagnosis of interstitial lung diseases (ILDs), lung tumors, and peripheral pulmonary lesions (PPLs). This study aims to compare cryobiopsy and forceps biopsy for the diagnosis of these lung pathologies with respect to efficacy and safety by performing a meta-analysis of updated evidence.

Methods

A number of databases, such as PubMed, Embase, Web of Science, the Cochrane Library, OVID, CNKI, and Wanfang database, were searched for eligible studies. Randomized and non-randomized comparative studies investigating the efficacy and safety of cryobiopsy vs. forceps biopsy for lung pathologies were included. Pooled results were calculated as an odds ratio (OR) or standardized mean difference (SMD) with 95% CI.

Results

A total of 39 studies, such as 9 RCTs with 3,586 biopsies (1,759 cryobiopsies and 1,827 flexible forceps biopsies) were analyzed. Cryobiopsy was associated with a significant increase in the diagnostic rates of ILDs (OR, 4.29; 95% CI, 1.85–9.93; p < 0.01), lung tumors (OR, 3.58; 95% CI, 2.60–4.93; p < 0.01), and PPLs (OR, 1.70; 95% CI, 1.23–2.34; p < 0.01). Cryobiopsy yielded significantly larger specimens compared with flexible forceps biopsy (SMD, 3.06; 95% CI, 2.37–3.74; p < 0.01). The cryobiopsy group had a significantly higher (moderate to severe) bleeding risk than the forceps group (OR, 2.17; 95% CI, 1.48–3.19; p < 0.01). No significant difference was observed in the incidence of pneumothorax between the groups (OR, 0.90; 95% CI, 0.44–1.85; p = 0.78).

Conclusion

Our results demonstrate that cryobiopsy is a safe and efficacious alternative to conventional forceps biopsy.

Cryobiopsy as a reliable technique for the preoperative identification of micropapillary/solid components in early-stage lung adenocarcinoma

OBJECTIVES

Micropapillary (MIP) and solid (SOL) subtypes of early-stage lung adenocarcinomas are associated with lymph node metastasis and local recurrence after limited resection. Preoperative identification of these components may influence the decisions of treatment strategy, additional lymph node evaluation, indication for limited resection, and extent of lymph node dissection. However, conventional biopsy specimens are insufficient for identifying these subtypes, especially MIP components. Cryobiopsy can collect larger tissue samples with fewer crush artifacts than conventional forceps biopsy, which would be helpful for detecting MIP/SOL components. Thus, this study aimed to analyze the feasibility of using cryobiopsy for MIP/SOL subtype detection.

MATERIAL AND METHODS

Consecutive patients who underwent surgery for clinical IA lung cancer following a preoperative diagnosis of adenocarcinoma by cryobiopsy at our institution between October 2017 and July 2019 were retrospectively examined. The concordance rate of MIP/SOL subtypes between the specimens obtained by cryobiopsy and surgery was investigated.

RESULTS

In total, 115 patients were evaluated. There were 26 (22.6%) and 14 (12.2%) patients with MIP and SOL subtypes, respectively. For concordance of MIP/SOL subtypes, the sensitivity was 65.7% (95% confidence interval [CI]: 57.7-65.7%). For the primary or secondary predominant patterns, a more satisfactory concordance rate of 72.2% (95% CI: 52.6-86.2%) was obtained. On assessing each subtype, high sensitivity was noted in SOL-predominant patterns (85.7%, 95% CI: 56.5%-96.0%) and MIP-secondary predominant patterns (83.3%, 95% CI: 45.8-97.0%). However, SOL-secondary predominant patterns revealed low sensitivity (0%, 95% CI, 0-38.2%). Overall, the MIP subtypes had higher sensitivity than the SOL subtypes (65.4% vs. 50.0%).

CONCLUSION

Cryobiopsy could be reliable for identifying MIP/SOL components, especially the MIP component, in clinical stage IA adenocarcinomas.

The Impact of Core Tissues on Successful Next-Generation Sequencing Analysis of Specimens Obtained through Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration

The success rate of next-generation sequencing (NGS) with specimens obtained through endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) among patients with lung cancer as well as the related clinical factors remain unclear. We aimed to determine the optimal number of punctures and core tissues during EBUS-TBNA for NGS in patients with non-small-cell lung cancer (NSCLC) as well as the association of chest computed tomography (CT) and EBUS findings with successful NGS. We retrospectively reviewed 156 consecutive patients with NSCLC who underwent EBUS-TBNA for NGS (Oncomine^TM Dx Target Test). Using the receiver operating characteristic curve, we calculated the optimal numbers of punctures and core tissues for NGS and evaluated CT and EBUS findings suggestive of necrosis and vascular pattern within the lesion. The success rate of NGS was 83.3%. The cut-off value for the number of core tissues was 4, and the sensitivity and specificity of successful NGS were 73.8% and 61.5%, respectively. Logistic regression analysis revealed that the number of core tissues (≥4) was the sole predictor of successful NGS. CT and EBUS findings were not associated with successful NGS. Bronchoscopists should obtain sufficient core tissues for successful NGS using EBUS-TBNA specimens.

Feasibility of next-generation sequencing (Oncomine™ DX Target Test) for the screening of oncogenic mutations in advanced non-small-cell lung cancer patients

BACKGROUND

The Oncomine™ Dx Target Test based on next-generation sequencing has been approved for the screening of oncogenic mutations in advanced non-small-cell lung cancer patients.

METHODS

We assessed the tissue sample factors that affect the success rate of Oncomine™ Dx Target Test companion diagnostics and the feasibility of using biopsy specimens for Oncomine™ Dx Target Test companion diagnostics in advanced non-small-cell lung cancer patients.

RESULTS

Ninety-nine biopsy samples were subjected to genetic testing using the Oncomine™ Dx Target Test companion diagnostics to detect v-raf murine sarcoma viral oncogene homologue B1 mutations (Cohort 1), and 136 biopsy samples were examined using Oncomine™ Dx Target Test companion diagnostics for the detection of multiple oncogenic mutations (Cohort 2) between July 2018 and April 2020. We retrospectively collected clinical and pathological data, including tissue size and tumour cell content. The success rate was 77% (76/99) in Cohort 1 and 93% (127/136) in Cohort 2. In Cohort 1, the success rate was significantly associated with the tumour cell content: the success rate was 63% for samples with a tumour cell content of <20%, whereas it was 83% for samples with a tumour cell content of 20% or higher (P = 0.0446). The tissue size also affected the success rate: a success rate of 57% was obtained for tissue sizes <4 mm2, whereas a success rate of 95% was obtained for tissue sizes of 4 mm2 or larger (P < 0.0001). In Cohort 2, the success rate was 100% when tumour specimens with a tissue size of 4 mm2 or larger were used.

CONCLUSIONS

Tissue size and tumour cell content were significantly associated with the success rate of Oncomine™ Dx Target Test companion diagnostics.

Cryobiopsy in Lung Cancer Diagnosis-A Literature Review

Optimizing the diagnosis of lung cancer represents a challenge, as well as a necessity, for improving the low survival of these patients. Flexible bronchoscopy with forceps biopsy is one of the key diagnostic procedures used for lung tumors. The small sample size and crush artifacts are several factors that can often limit access to a complete diagnosis, therefore leading to the need of repeating the bronchoscopy procedure or other invasive diagnostic methods. The bronchoscopic cryobiopsy is a recent technique that proved its utility in the diagnosis of both endobronchial and peripheral lung tumors. In comparison with conventional forceps biopsy, studies report a higher diagnostic yield and a superior quality of the collected samples for both the histopathological and the molecular diagnosis of lung cancer. This method shows promising results in sampling lung tissue, alone, or in conjunction with fluoroscopy or radial endobronchial ultrasound (r-EBUS). With a good safety and cost-benefit profile, this novel method has the potential to improve the diagnosis, and therefore the management of lung cancer patients. The objective of this narrative review is to provide a comprehensive review of the recent data regarding the advantages of cryobiopsy and r-EBUS in lung cancer diagnosis.

Diagnosis of miliary nodules as lung adenocarcinoma by cryobiopsy: A case report

A 62‐year‐old woman with rheumatoid arthritis and a history of receiving immunosuppressant therapy had a recurrence of lung adenocarcinoma with EGFR L858R mutation. Following 14 months of treatment with erlotinib, computed tomography (CT) findings revealed the presence of small diffuse nodules. Bronchoscopy was performed as metastasis was suspected; however, this was not detected on lung biopsy with forceps. Transbronchial lung cryobiopsy (TBLC) succeeded in detecting metastatic adenocarcinoma, and T790M and L858R gene mutations. Pathological examination revealed a cluster of tumor cells in the intralobular interstitial areas, which was consistent with the CT findings. This report provides important information regarding the role of TBLC in diagnosing metastatic cancer, such as diffuse small miliary nodules, and its genetic mutations.

Suitability of Bronchoscopic Biopsy Tissue Samples for Next-Generation Sequencing

A sufficiently large tissue sample is required to perform next-generation sequencing (NGS) with a high success rate, but the majority of patients with advanced non-small-cell lung cancer (NSCLC) are diagnosed with small biopsy specimens. Biopsy samples were collected from 184 patients with bronchoscopically diagnosed NSCLC. The tissue surface area, tumor cell count, and tumor content rate of each biopsy sample were evaluated. The impact of the cut-off criteria for the tissue surface area (≥1 mm2) and tumor content rate (≥30%) on the success rate of the Oncomine Dx Target Test (ODxTT) was evaluated. The mean tissue surface area of the transbronchial biopsies was 1.23 ± 0.85 mm2 when small endobronchial ultrasonography with a guide sheath (EBUS-GS) was used, 2.16 ± 1.49 mm2 with large EBUS-GS, and 1.81 ± 0.75 mm2 with endobronchial biopsy (EBB). The proportion of samples with a tissue surface area of ≥1 mm2 was 48.8% for small EBUS-GS, 79.2% for large EBUS-GS, and 78.6% for EBB. Sixty-nine patients underwent ODxTT. The success rate of DNA sequencing was 84.1% and that of RNA sequencing was 92.7% over all patients. The success rate of DNA (RNA) sequencing was 57.1% (71.4%) for small EBUS-GS (n = 14), 93.4% (96.9%) for large EBUS-GS (n = 32), 62.5% (100%) for EBB (n = 8), and 100% (100%) for endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) (n = 15). Regardless of the device used, a tissue surface area of ≥ 1 mm2 is adequate for samples to be tested with NGS.

Pleural staging using local anesthetic thoracoscopy in dry pleural dissemination and minimal pleural effusion

BACKGROUND

Dry pleural dissemination (DPD) and minimal (<10 mm thick) pleural effusion (PE) may be discovered intraoperatively as unexpected metastases. A definitive diagnostic procedure such as pleural biopsy is rarely attempted in such patients preoperatively. We retrospectively investigated the use and safety of local anesthetic thoracoscopy (LAT) as a pleural staging tool in the diagnosis of DPD and minimal PE.

METHODS

We reviewed 18 patients with non-small cell lung cancer (radiological DPD and minimal PE in 13 and five patients, respectively) who underwent LAT using a flex-rigid pleuroscope for pleural staging from April 2015 to September 2020.

RESULTS

The median age of the patients was 72 years. Nine patients (50%) were men. The dominant histological type was adenocarcinoma (n = 16). Three patients each with radiological DPD and minimal PE had visible PE on the LAT. Pleural biopsy was performed in the 16 cases in which pleural abnormalities were identified. On pleural staging, five cases were diagnosed without pleural dissemination (M0), and 13 cases were diagnosed with pleural dissemination (M1a). Only one case in which the lesion could not be identified because of pleural adhesions was false-negative. The success rates for pleural staging, sensitivity, specificity, positive predictive value, and negative predictive value were 94.4% (17/18), 92.8% (13/14), 100% (4/4), 100% (13/13), and 80.0% (4/5), respectively. There were no lung lacerations or other severe complications caused by the procedure or during blunt dissection.

CONCLUSION

LAT might be a useful tool for accurate pleural staging in cases with DPD and minimal PE suspected radiologically.

A case report of pneumonic-type adenocarcinoma diagnosed by transbronchial cryobiopsy after the patient's death

RATIONALE

Due to its nonspecific manifestations, pneumonic-type adenocarcinoma can be easily misdiagnosed as pneumonia, tuberculosis, or other diseases, especially in developing countries where many patients in the early stage refuse invasive examinations. Early recognition of pneumonic-type adenocarcinoma is essential.

PATIENT CONCERNS

We report a case of pneumonia lung adenocarcinoma diagnosed by frozen lung biopsy after death.

DIAGNOSES

A 75-year-old male patient was admitted to the hospital on April 24, complaining of 5 months of recurrent coughing, expectoration, and panting, and his symptoms had been worsening over the past month.

INTERVENTIONS

After obtaining informed consent from the patient's family, transbronchial cryobiopsy was performed at the bedside.

OUTCOMES

After a positive rescue, the patient died. Pathological examination indicated adenocarcinoma.

LESSONS

At present, surgery is still the first choice for the treatment of pneumonic lung cancer, and early diagnosis can remove the tumor as much as possible. Transbronchial cryobiopsy can be used for the collection of pathological samples, especially for the early diagnosis of pneumonic lung cancer.

Comparison of adequacy between transbronchial lung cryobiopsy samples and endobronchial ultrasound-guided transbronchial needle aspiration samples for next-generation sequencing analysis

Background

Most lung cancer patients present with lesions in both lung fields and lymphadenopathy. Thus, transbronchial lung cryobiopsy (TBLC) and endobronchial ultrasound‐guided transbronchial needle aspiration (EBUS‐TBNA) are commonly performed for diagnosing lung cancer. However, the adequacy of these samples for next‐generation sequencing (NGS) analysis remains unclear. This study aimed to compare the adequacy between TBLC and EBUS‐TBNA samples for NGS analysis.

Methods

This retrospective cohort study included patients whose lung samples were collected via TBLC or EBUS‐TBNA and analyzed using NGS. Out of 46 genes, the number of genes in TBNA and TBLC samples that could not be assessed via NGS analysis was mainly evaluated.

Results

A total of 37 patients were included and classified into two groups (TBLC group, n = 18 and TBNA group, n = 19). The mean number of genes that could not be evaluated via NGS analysis was significantly lower in the TBLC group than in the TBNA group (0.9 vs. 10.3, P = 0.024). The median total area of tumor cells in TBLC samples was significantly greater than that in TBNA samples (6.3 [1.6–4.2] vs. 2.6 [0.2–17.3] mm², P < 0.01). In the TBNA group, there were two fully inadequate samples for NGS analysis with a high degree of cell crush or low tumor content, while there was no fully inadequate sample in the TBLC group.

Conclusions

TBLC is more effective in obtaining adequate samples for NGS analysis than EBUS‐TBNA. TBLC should be performed to obtain adequate samples for NGS analysis in lung cancer patients with target lesions in lung fields, even if they have lymphadenopathy.

Key points

Significant findings of the study

The mean number of genes that could not be evaluated was significantly lower in TBLC samples than in EBUS‐TBNA samples (0.9 vs. 10.3, P = 0.024). TBLC could obtain adequate samples with a high concentration of uncrushed tumor cells for NGS.

What this study adds

To obtain samples for NGS analysis, the use of TBLC should be aggressively considered in lung‐cancer patients with target lesions located in lung fields, even if they have lymphadenopathy.

Suitability of transbronchial brushing cytology specimens for next-generation sequencing in peripheral lung cancer

Next‐generation sequencing (NGS) enables the diagnosis of large numbers of gene aberrations during one examination, and precision medicine has been developed for patients with advanced non–small cell lung cancer (NSCLC). However, peripheral lung lesions account for the majority of advanced lung cancers, especially lung adenocarcinoma. In these cases, it is difficult to obtain tissue samples which contain sufficient tumor cells by transbronchial biopsy (TBB) with forceps. Even when the target lesions are quite small, bronchial brushing can obtain enough tumor cells by endobronchial ultrasonography using guide sheath (EBUS‐GS). In this study, we investigate the suitability of bronchial brushing cytology specimens obtained by EBUS‐GS‐TBB to evaluate the correlation between the success rate of NGS and extracted DNA/RNA yields according to biopsy method. We prospectively collected 222 tumor samples obtained from patients with advanced lung cancer. All patients were enrolled in a prospective nationwide genomic screening project for lung cancer (LC‐SCRUM‐Japan/Asia). Genomic data were obtained from the clinico‐genomic database of LC‐SCRUM‐Japan/Asia. The extraction yields of DNA/RNA from samples obtained by EBUS‐GS‐TBB were relatively low compared with tissue samples. The success rate of DNA sequencing for EBUS‐GS‐TBB was 97.9%, with no significant differences between biopsy methods. The success rate of RNA sequencing for EBUS‐GS‐TBB was 80.4%, which was relatively low compared with surgical biopsy samples (P = 0.069). However, some rare oncogenic driver aberrations were detected from these specimens. This study demonstrated that cytology samples obtained by transbronchial brushing with EBUS‐GS‐TBB were suitable for NGS analysis.

Feasibility and utility of transbronchial cryobiopsy in precision medicine for lung cancer: Prospective single-arm study

Cryoprobe is a novel transbronchial biopsy (TBB) tool that yields larger tissue samples than forceps. Pathological diagnosis and biomarker analysis, such as genetic alterations and programmed death‐ligand 1 (PD‐L1) expression, are paramount for precision medicine against lung cancer. We evaluated the safety and usefulness of cryoprobe TBB for lung cancer diagnosis and biomarker analysis. In this single‐center, prospective single‐arm study, patients suspected of having or diagnosed with primary lung cancer underwent cryoprobe TBB using flexible bronchoscopy after conventional forceps TBB from the same lesion. Cryoprobe TBB was performed in 121 patients. The incidence rate of severe bleeding and serious adverse events (4% [90% confidence interval: 2%‐9%]) was significantly lower than the expected rate (20% with 30% threshold, P < 0.01). Combining both central and peripheral lesions, the diagnostic yield rate of cryoprobe samples was 76% and that of forceps samples was 84%. Compared with forceps TBB samples, cryoprobe TBB samples were larger (cryoprobe 15 mm² vs forceps 2 mm²) and resulted in a larger proportion of definite histomorphological diagnosis (cryoprobe 86% vs forceps 74%, P < 0.01), larger amounts of DNA extracted from samples (median: cryoprobe, 1.60 µg vs forceps, 0.58 µg, P = 0.02) and RNA (median: cryoprobe, 0.62 µg vs forceps, 0.17 µg, P < 0.01) extracted from samples, and tended to yield greater rates of PD‐L1 expression >1% (51% vs 42%). In conclusion, cryoprobe is a safe and useful tool for obtaining lung cancer tissue samples of adequate size and quality, which allow morphological diagnosis and biomarker analysis for precision medicine against lung cancer.