Safety profile and risk factors for bleeding in transbronchial cryobiopsy using a two-scope technique for peripheral pulmonary lesions

Fatal airway obstruction due to endobronchial bleeding post cryobiopsy: a case report

Cryobiopsy offers an advantage because of the extraction of more extensive tissue and enhanced diagnostic accuracy. However, the risk of bleeding from the biopsy site is higher. We report a lung tumor patient who experienced bleeding in the right main bronchus after cryobiopsy. Suctioning was performed, cold saline was administered, and the bleeding stopped. Five minutes after the procedure, the patient experienced desaturation. A re-bronchoscopy found massive bleeding in the right main bronchus which spread to the left main bronchus. Suctioning was performed, cold saline and epinephrine were administered. Before further treatment was given, the patient got cardiac arrest and he was treated in the intensive care unit. This highlighted the importance of training and considering the additional precautions for bleeding control. Intensive monitoring of the patients is needed when performing cryobiopsy to prepare for the early management of complications, especially for those patients with risk factors for bleeding in cryobiopsy.

Safety and efficacy of transbronchial cryobiopsy for elderly lung cancer patients

BACKGROUND

The increasing prevalence of lung cancer in the elderly population necessitates a closer evaluation of diagnostic and therapeutic approaches. This study aimed to compare the safety and diagnostic efficacy of transbronchial lung cryobiopsy (TBLC) between patients ≥ 80 years and younger patients.

METHODS

A retrospective review was conducted of 96 patients diagnosed with peripheral lung cancer who underwent TBLC between April 2021 and October 2023. The patients were categorized into two groups: the elderly group (age ≥ 80 years, n = 20) and younger group (age < 80 years; n = 76). Data regarding the biopsy yield, complications, and feasibility of molecular analyses were collected and analyzed.

RESULTS

The diagnostic yield of TBLC was comparable between the elderly and younger groups (95% vs. 89.5%, p = 0.679). Biomarker testing, including programmed death-ligand 1 expression and genetic mutations, were feasible in all cases diagnosed with cancer using TBLC samples. No significant differences were observed in major complications such as pneumothorax or bleeding.

CONCLUSIONS

TBLC was found to be a safe and effective diagnostic tool for peripheral lung cancer in elderly patients and provided adequate samples for molecular testing. Since the complication rates did not significantly differ between the two age groups, age alone should not be considered a contraindication for the procedure.

Abstracts of the Italian Society of Thoracic Endoscopy (SIET) 2024 Annual Congress

We are pleased to introduce the abstracts of the XXIII National Congress of the Italian Society of Thoracic Endoscopy (SIET), which will be held in Florence from 17 to 19 October 2024. The principal objectives of SIET are to (1) Promote research and innovation in the fields of thoracic surgery and endoscopy, facilitating the development and implementation of innovative techniques and technologies; (2) Provide education and training for surgeons, endoscopists, pulmonologists and other related specialties; and (3) Facilitate the exchange of knowledge with the aim of creating a cohesive and active scientific community. The Congress will address the integration of traditional surgical and endoscopic techniques with emerging technologies, with the goal of promoting innovation and education among professionals. The theme of integration will be explored throughout the programme, with a particular focus on the collaborative efforts of different medical specialties to improve patient outcomes. This event will host a multidisciplinary cohort comprising thoracic surgeons, endoscopists, pulmonologists, oncologists, pathologists, radiologists and anaesthetists, who will assume a pivotal role in the multidisciplinary sessions of the scientific programme. The Congress will include several core areas of expertise, including lung cancer, interventional endoscopy, pathology, and upper airway reconstruction. Emphasis will be placed on both the theoretical aspects of these subjects and their practical applications in patient care. The theme of integration will be explored throughout the programme, with particular attention on the impact of recent technological developments in the fields of thoracic surgery and endoscopy. Additionally, the Congress will examine the contributions of allied health professionals, including nurses, physiotherapists, and speech pathologists, to patient care.

Feasibility of Cryobiopsy Specimen Retrieval Through Standard Guide Sheath for Peripheral Pulmonary Lesions Without Bronchoscope Removal

BACKGROUND

Transbronchial cryobiopsy is a promising technique for biopsy of peripheral pulmonary lesions (PPL). However, cryobiopsy specimen retrieval can pose problems due to the risk of bleeding during the blind period when the bronchoscope and cryoprobe are removed en bloc. Artificial airways and prophylactic balloon placement are risk-reducing measures, but the latter is challenging in upper lobe PPL. Specimen retrieval through standard guide sheath (GS) system without the need for bronchoscope removal may now be feasible with the ultrathin cryoprobe.

METHODS

Retrospective review of radial endobronchial ultrasound (rEBUS)-guided transbronchial cryobiopsy for PPL cases in which cryobiopsy specimen was retrieved through the GS over a 6-month period.

RESULTS

Twenty patients were included with an overall median age of 66.50 (IQR: 53.0 to 76.7). The median procedural time was 30 (IQR: 25.0 to 33.7) minutes. Median target size was 3.20 (IQR: 2.17 to 4.84) cm with 85% of lesions demonstrated "within" rEBUS orientation. Overall technical feasibility was 85% with median cryoactivation of 4.0 (IQR: 3.0 to 4.0) seconds. No specimen was retrieved in 3 patients. The diagnostic yield for forceps and cryobiopsy was 70% and 60%, respectively, and the combined diagnostic yield was 85% (P<0.01 vs. forceps biopsy). Median aggregate size for forceps and cryobiopsy was 8.0 (IQR: 5.3 to 10.0) and 4.5 (IQR: 2.3 to 7.0) mm respectively (P<0.01). No pneumothorax was reported and mild self-limiting bleeding was encountered in 30% of cases.

CONCLUSION

Retrieval of cryoprobe through standard GS appears to be a safe and feasible method that can simplify the transbronchial cryobiopsy procedure and complement forceps biopsy in specific cases.

Diagnostic efficacy of cryobiopsy for peripheral pulmonary lesions with ground-glass opacity: a propensity score-matched analysis

Background

Peripheral pulmonary lesions (PPLs) with ground-glass opacity (GGO) are generally difficult to diagnose via bronchoscopy. Cryobiopsy, a recently introduced technique, provides quantitatively and qualitatively superior tissues compared with conventional biopsy methods and can improve diagnostic outcomes. However, its diagnostic accuracy has not been specifically investigated. Therefore, this study aimed to determine whether the combined use of cryobiopsy improves the diagnostic yield for PPLs with GGO.

Methods

Consecutive patients who underwent bronchoscopy combined with radial endobronchial ultrasound and virtual bronchoscopic navigation for PPLs with GGO were retrospectively reviewed between June 2014 and May 2020. Cryobiopsy was introduced at our institution in June 2017. Patients who underwent only conventional biopsy (forceps and/or needle aspiration) between June 2014 and May 2017 were classified as the conventional group, whereas those who underwent cryobiopsy with or without conventional biopsy between June 2017 and May 2020 were categorized as the "cryo" group. The diagnostic performance of the two groups was compared using propensity score-matched analysis.

Results

Overall, 553 cases were identified, including 250 and 303 in the cryo and conventional groups, respectively. Propensity scoring was implemented to match lesion characteristics and intraprocedural findings, leading to the selection of 232 pairs of cases for each matched (m) group. The diagnostic yield in the m-cryo group was significantly higher than that in the m-conventional group [88.8% vs. 63.8%, odds ratio: 4.50 (95% confidence interval: 2.76-7.33), P<0.001]. Although the incidence of grade 2 and 3 bleeding in the m-cryo group was higher than that in the m-conventional group (40.5% vs. 8.6% and 2.6% vs. 0.4%, respectively; P<0.001), grade 4 bleeding was not reported.

Conclusions

The combined use of cryobiopsy provides improved diagnostic yield for PPLs with GGO compared with conventional biopsy methods.

Value of ultrathin bronchoscope in improving the endobronchial ultrasound localization rate and diagnosing peripheral pulmonary nodules by cryobiopsy

BACKGROUND

A 3.0-mm ultrathin bronchoscope (UTB) with a 1.7-mm working channel provides better accessibility to peripheral bronchi. A 4.0-mm thin bronchoscope with a larger 2.0-mm working channel facilitates the use of a guide sheath (GS), ensuring repeated sampling from the same location. The 1.1-mm ultrathin cryoprobe has a smaller diameter, overcoming the limitation of the size of biopsy instruments used with UTB. In this study, we compared the endobronchial ultrasound localization rate and diagnostic yield of peripheral lung lesions by cryobiopsy using UTB and thin bronchoscopy combined with GS.

METHODS

We retrospectively evaluated 133 patients with peripheral pulmonary lesions with a diameter less than 30 mm who underwent bronchoscopy with either thin bronchoscope or UTB from May 2019 to May 2023. A 3.0-mm UTB combined with rEBUS was used in the UTB group, whereas a 4.0-mm thin bronchoscope combined with rEBUS and GS was used for the thin bronchoscope group. A 1.1-mm ultrathin cryoprobe was used for cryobiopsy in the two groups.

RESULTS

Among the 133 patients, peripheral pulmonary nodules in 85 subjects were visualized using r-EBUS. The ultrasound localization rate was significantly higher in the UTB group than in the thin bronchoscope group (96.0% vs. 44.6%, respectively; P < 0.001). The diagnostic yield of cryobiopsy specimens from the UTB group was significantly higher compared to the thin bronchoscope group (54.0% vs. 30.1%, respectively; p = 0.006). Univariate analysis demonstrated that the cryobiopsy diagnostic yields of the UTB group were significantly higher for lesions ≤ 20 mm, benign lesions, upper lobe lesions, lesions located lateral one-third from the hilum, and lesions without bronchus sign.

CONCLUSIONS

Ultrathin bronchoscopy combined with cryobiopsy has a superior ultrasound localization rate and diagnostic yield compared to a combination of cryobiopsy and thin bronchoscopy.

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.

Modified two-scope technique for transbronchial lung cryobiopsy of peripheral pulmonary lesions

Bleeding mitigation is an important part of any transbronchial lung cryobiopsy (TBLC) procedure, either for interstitial lung disease (ILD) or peripheral pulmonary lesions (PPL). The two-scope technique has been previously described for ILD and PPL-TBLC, but it has its own limitations and technical and logistical complexities. In this case series, we describe a modified two-scope technique that enhances the conventional two-scope technique by maintaining a small equipment footprint and longer bronchoscopic vision without the need for intra-procedure switching of bronchoscopes. Three cases of PPLs were navigated by standard radial endobronchial ultrasound and biopsied with the 1.1 mm flexible ultrathin cryoprobe. All cases achieved a conclusive diagnosis with adequate specimens for immunohistochemical staining and molecular analysis; only Grade 1 bleeding reported in two cases. The challenges and limitations of this modified two-scope technique were also explored in this series.

Novel method of attaching a suction tube externally to a tracheal tube as an insertion route for a Fogarty catheter in cryobiopsy: Retrospective comparative study

BACKGROUND

Cryobiopsy use is anticipated to become more common in diagnosing lung diseases. In Japan, inserting a Fogarty catheter through a suction channel above the endotracheal tube's cuff for hemostasis is common practice. However, the rigid nature of the endotracheal tube poses challenges to tracheal intubation using a bronchoscope. The endotracheal tube cuff must be removed to prevent interference during Fogarty catheter insertion. To simplify the procedure and enhance safety, we devised and implemented a method of inserting a hemostatic Fogarty catheter with a suction tube externally attached to a softer endotracheal tube. This study aimed to evaluate the sustainability of this Fogarty catheter insertion method using suction tubes.

METHODS

The hemostatic Fogarty catheter insertion method was retrospectively validated. We compared outcomes between 60 patients who underwent the conventional method with a suction channel above the cuff and 50 patients who underwent the novel approach with an externally attached suction tube.

RESULTS

The physicians performing bronchoscopy and inserting the Fogarty catheter in the group in which the suction tube was externally attached for Fogarty catheter insertion had little experience. However, the overall bronchoscopy time was shorter; the two groups showed no significant differences in complications.

CONCLUSION

Regarding cryobiopsy procedures, using an externally attached suction tube for Fogarty catheter insertion was practical and comparable to the conventional method of using a suction channel above the cuff. This method made the procedure more simple and safe.

Advanced Bronchoscopic Diagnostic Techniques in Lung Cancer

The increasing incidence of incidental pulmonary nodules necessitates effective biopsy techniques for accurate diagnosis and treatment planning. This paper reviews the widely used advanced bronchoscopic techniques, such as radial endobronchial ultrasound-guided transbronchial lung biopsy, electromagnetic navigation bronchoscopy, and the cutting-edge robotic-assisted bronchoscopy. In addition, the cryobiopsy technique, which can enhance diagnostic yield by combination with conventional biopsy tools, is described for application to peripheral pulmonary lesions and mediastinal lesions, respectively.

Bronchial occlusion with endobronchial Watanabe spigots using a two-scope technique for massive haemoptysis

Massive haemoptysis is a life-threatening condition whose cause needs to be identified rapidly so that prompt interventions can ensue. Bronchial occlusion with endobronchial Watanabe spigots (EWSs) may be useful when endovascular treatment or surgery proves to be difficult. An 84-year-old woman developed massive haemoptysis during percutaneous mitral valve repair for refractory heart failure due to severe mitral regurgitation (MR). Interventional radiology (IVR) and surgery were contraindicated, and bronchial occlusion with EWSs was attempted to control bleeding. The bleeding was so persistent that it was difficult to secure the visual field without aspiration with a bronchoscope. Herein, we report a two-scope technique, also used in cryobiopsy of peripheral lung lesions, to control bleeding and perform bronchial occlusion with EWSs.

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.

Cryodebulking to Relieve Critical Airway Narrowing Due to a Central Airway Tumor at the Carina: A Case Report and Literature Review

Central airway tumors presenting as critical airway stenosis is a medical emergency. Employing a cryoprobe, we successfully debulked a central airway tumor, providing rapid relief to a patient who came to the emergency room with severe breathlessness, hemoptysis, and respiratory failure. The current report underscores the efficacy of cryodebulking as an immediate and minimally invasive technique and a compelling alternative to conventional heat-based therapies.

Safety and risk factors for bleeding complications of radial probe endobronchial ultrasound-guided transbronchial biopsy

BACKGROUND

Radial probe endobronchial ultrasound (radial EBUS) is widely used to diagnose pulmonary lesions; however, the diagnostic value of radial EBUS-guided transbronchial biopsy (TBB) varies, and its complications (especially the risk of bleeding) are not properly understood.

OBJECTIVES

In this study, we evaluated the diagnostic performance and rate of complication of this procedure, and investigated the risk factors associated with the procedure-related bleeding events.

DESIGN

A retrospective cohort study.

METHODS

This was a retrospective study that included consecutive patients who underwent radial EBUS-guided TBB. Radial EBUS was performed under moderate sedation in inpatients or outpatients. The severity of bleeding was graded using the standardized definitions of bleeding.

RESULTS

Of 133 patients (median age, 69 years; men 57.1%) included, 41 were outpatients (30.8%). The diagnostic accuracy, sensitivity, and specificity for malignancy were 76.1% (89/117), 71.1% (69/97), and 100% (20/20), respectively. The diagnostic accuracy ranged from 66.9% to 79.0%, depending on the classification of undiagnosed cases as either false negatives or true negatives. Twenty-seven patients (20.3%) developed complications (pneumothorax, 3; pneumonia, 5; complicated pleural effusion, 2; bleeding event grade 2 or higher, 21). Of the 41 outpatients, two developed complications (pneumothorax without intervention, 1; grade 2 bleeding event, 1). Of the 21 patients (15.8%) with procedure-related bleeding events, 18 had grade 2, and three had grade 3 bleeding complications. In multivariate analysis, a large size of ⩾30 mm (adjusted odds ratio (OR), 5.09; p = 0.03) and central lesion (adjusted OR, 3.67; p = 0.03) were significantly associated with the risk of grade 2 or higher bleeding events.

CONCLUSION

Our results suggest that radial EBUS-guided TBB is an accurate and safe method for diagnosing pulmonary lesions. Clinically significant procedure-related bleeding was rare. The central location and larger size (⩾30 mm) of pulmonary lesions were risk factors for grade 2 or higher bleeding events.

Diagnostic Value of Transbronchial Lung Cryobiopsy Using an Ultrathin Cryoprobe and Guide Sheath for Peripheral Pulmonary Lesions

BACKGROUND

The addition of cryobiopsy to conventional biopsy methods improves the diagnostic yield of peripheral pulmonary lesions. Moreover, cryobiopsy with a guide sheath (GS) provides additional diagnostic benefits. Semi-real-time biopsy can be repeatedly performed using conventional biopsy devices and a GS, and subsequent cryobiopsy can be easily performed at the same location. Recently, a disposable 1.1 mm-diameter ultrathin cryoprobe has been developed and can be used with a 1.95 mm GS in a 2.0 mm working channel. In this study, we evaluated the diagnostic performance of transbronchial lung cryobiopsy (TBLC) with the 1.1 mm cryoprobe and a GS in patients with peripheral pulmonary lesions.

METHODS

We retrospectively reviewed the medical records of patients who underwent endobronchial ultrasound transbronchial lung biopsy with a guide sheath and TBLC from July 23, 2021 to April 30, 2022 at Chungnam National University Hospital.

RESULTS

Of a consecutive series of 229 patients, 199 were included. The diagnostic yields of forceps biopsy and cryobiopsy were 65.3% (130/199) and 84.4% (168/199), respectively, and the total diagnostic yield was 91.5% (182/199) ( P <0.001 vs. forceps biopsy). Multivariate analysis showed that solid lesion morphology [adjusted odds ratio (OR) 3.659, P =0.002] was associated with a significantly greater diagnostic yield of cryobiopsy, whereas a lesion diameter >20 mm ( P =0.026; adjusted OR 3.816) and 'within' orientation ( P =0.004; adjusted OR 6.174) were associated with a significantly greater overall diagnostic yield.

CONCLUSION

TBLC using an ultrathin cryoprobe and GS markedly improves the diagnostic yield.

Transbronchial cryobiopsy for small peripheral pulmonary lesions using endobronchial ultrasonography and an ultrathin bronchoscope

BACKGROUND

Transbronchial biopsy using an ultrathin bronchoscope (UTB) has a high diagnostic yield for peripheral pulmonary lesions (PPLs). When combined with peripheral transbronchial needle aspiration (pTBNA), it improves the diagnostic yield of "adjacent to" radial endobronchial ultrasonography (rEBUS) findings. However, pTBNA is a complicated technique, and the specimen volume is often inadequate for diagnostic and multiplex analyses. Recently, transbronchial cryobiopsy (TBCB) using a 1.1-mm cryoprobe that could be inserted into an UTB has been available. We investigated whether TBCB combined with forceps biopsy using a 1.1-mm cryoprobe with an UTB improved the diagnostic yield of "adjacent to" lesions.

METHODS

The data of 66 consecutive patients who underwent TBCB and forceps biopsy using UTB (hemostasis using two-scope method) under rEBUS for small PPLs (≤30 mm) were retrospectively analyzed. The histological diagnosis rate using TBCB and forceps biopsy, TBCB alone, or forceps biopsy alone was compared between cases where the rEBUS probe was "within" and "adjacent to" lesions.

RESULTS

The diagnosis rate using TBCB and forceps biopsy was 81.8 % for all lesions ("within" vs. "adjacent to" cases: 88.4 % vs. 69.6 %; p = 0.093). The corresponding rate using TBCB alone was 80.3 % (86.0 % vs. 69.6 %; p = 0.19), and that using forceps biopsy alone was 62.1 % (74.4 % vs. 39.1 %; p = 0.008). Bleeding leading to discontinuation of the examination occurred in four (6.1 %) patients; however, in all cases, bleeding could be controlled endoscopically.

CONCLUSION

Forceps biopsy with TBCB during ultrathin bronchoscopy for small PPLs improved the diagnostic yield when the lesions were adjacent to the rEBUS probe.

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).

Diagnostic Utility and Safety of Non-Intubated Cryobiopsy Technique Using a Novel Ultrathin Cryoprobe in Addition to Conventional Biopsy Techniques for Peripheral Pulmonary Lesions

BACKGROUND

Transbronchial cryobiopsy enables high-quality sample collection around the probe tip. Meanwhile, existing cryoprobes have less flexibility and a higher risk of bleeding. The ultrathin cryoprobe with a 1.1-mm diameter addresses these problems and allows specimens to be directly retrieved through the working channel of a thin bronchoscope.

OBJECTIVE

This study evaluated the diagnostic utility and safety of non-intubated cryobiopsy using an ultrathin cryoprobe added to conventional biopsy for diagnosing peripheral pulmonary lesions (PPLs).

METHODS

The data of patients who underwent conventional biopsy followed by non-intubated cryobiopsy to retrieve specimens through the thin bronchoscope's working channel for diagnosing PPLs at Osaka Metropolitan University Hospital from July 2021 to June 2022 were retrospectively collected. They were analyzed to evaluate the diagnostic utility and safety of adding non-intubated cryobiopsy to conventional biopsy for PPLs. The characteristics of PPLs that obtain additional diagnostic benefits from cryobiopsy over conventional biopsy were also investigated.

RESULTS

The analysis included 113 patients. The diagnostic yields of conventional biopsy and non-intubated cryobiopsy were 70.8% and 82.3%, respectively (p = 0.009). The total diagnostic yield was 85.8%, higher than conventional biopsy alone (p < 0.001). Although one moderate bleeding occurred, no severe complications developed. The additional diagnostic benefits of non-intubated cryobiopsy over conventional biopsy were demonstrated when the radial endobronchial ultrasound (R-EBUS) showed "adjacent to" (60.3% vs. 82.8%, p = 0.017).

CONCLUSIONS

Non-intubated cryobiopsy using an ultrathin cryoprobe has high diagnostic utility and safety for diagnosing PPLs, with additional diagnostic benefits over conventional biopsy depending on the R-EBUS image.

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.

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.

Evaluation of deployment capability of a novel outside-the-scope, detachable catheter system for ablation of lung lesions in ex vivo human lung models

Objectives

Effective transbronchial ablation of lung nodules requires precise catheter delivery to the target lesion and freedom from the bronchoscope for safety throughout the procedure and to allow for multiple catheter insertions. A fully detachable, outside-the-scope (OTS) probe system was developed that attaches to a flexible bronchoscope. Using this system, the operator can deploy the probe in the target and completely detach it from the scope. Our aim was to demonstrate the endobronchial deployment accuracy and feasibility of an OTS, detachable, simulated ablation catheter driven to peripheral lung targets in ex vivo–ventilated human lung models.

Methods

A balloon catheter inflated with radiopaque contrast was used as a simulated peripheral target in freshly explanted lungs from lung transplant recipients. A simulated ablation catheter was positioned outside and aligned to the tip of the bronchoscope using the OTS system. Under fluoroscopic guidance, the bronchoscope and the catheter were driven toward the target in mechanically ventilated lungs. Once the catheter tip was confirmed within the target, the OTS system was released and the probe was detached from the scope. The bronchoscope was retracted and fluoroscopy was used to confirm the position of the catheter.

Results

Twelve peripheral targets were simulated. The ablation catheter was successfully deployed with its tip positioned within 5 mm from the target and confirmed stability during multiple cycles of ventilation.

Conclusions

A novel, detachable, OTS system can be successfully deployed in peripheral lung targets with potential clinical applications for multiple procedures in advanced bronchoscopy where scope freedom is advantageous.