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ORIGINAL ARTICLE
Histological diagnosis of interstitial lung diseases by cryo-transbronchial biopsy OREN FRUCHTER,1,3 LUDMILA FRIDEL,2 BAYYA ABED EL RAOUF,1 NADER ABDEL-RAHMAN,1 DROR ROSENGARTEN1 AND MORDECHAI R. KRAMER1,3 1
Institute of Pulmonary, and 2Department of Pathology, Rabin Medical Center, Petah Tiqwa, and 3The Sackler School of Medicine, Tel-Aviv University, Tel Aviv, Israel
ABSTRACT Background and objective: The gold standard for the histological diagnosis of interstitial lung diseases (ILD) is an open lung biopsy (OLB). Tissue samples obtained by forceps transbronchial lung biopsies (TBB) are usually too small. We aim to evaluate the efficacy and safety of cryo-TBB for the diagnosis of ILD and to explore its role as substitute for OLB. Methods: Seventy-five patients (mean age 56.2 years) with clinical and radiological features suggestive of ILD underwent cryo-TBB under moderate sedation. The diagnostic contribution on the work-up of suspected ILD was assessed. Results: No major complications occurred during cryo-TBB procedures. The mean cross-sectional area of the biopsy specimen obtained was 9 mm2 with an average of 70% alveolated tissue. The most common pathological diagnoses were idiopathic nonspecific interstitial pneumonitis (n = 22), cryptogenic organizing pneumonia (n = 11) and usual interstitial pneumonitis (n = 7). There were three patients of pulmonary Langerhans cell histiocytosis and one patient of pulmonary lymphangioleiomyomatosis. A definite and probable clinicopathological consensus diagnosis was possible in 70% and 28% of patients, respectively. In only 2% of patients’ diagnosis could not be established. Conclusions: Cryo-TBB is a safe and effective minimally invasive modality for the diagnosis of ILD. No OLB is needed in the majority of patients. Key words: alveolar proteinosis, bronchoscopy and interventional techniques, interstitial lung disease, nonspecific interstitial pneumonitis, usual interstitial pneumonitis. Abbreviations: COP, cryptogenic organizing pneumonia; DIP, desquamative interstitial pneumonia; HRCT, high-resolution computed tomography; ILD, interstitial lung diseases; IPF, idiopathic pulmonary fibrosis; LAM, lymphangioleiomyomatosis; Correspondence: Oren Fruchter, Interventional Bronchoscopy, The Pulmonary Division, Rabin Medical Center, Beilinson Hospital, Petach Tikva 49100, Israel. Email: [email protected] Received 17 December 2013; invited to revise 29 January and 21 February 2014; revised 30 January and 23 February 2014; accepted 23 February 2013 (Associate Editor: Toby Maher). Article first published online: 20 April 2014 © 2014 Asian Pacific Society of Respirology
SUMMARY AT A GLANCE Cryo-transbronchial biopsy provides diagnostic material that enables a histological diagnosis in patients with interstitial lung diseases and obviates the need for open lung biopsy in the majority of patients.
NSIP, nonspecific interstitial pneumonitis; OLB, open lung biopsy; PLCH, pulmonary Langerhans cell histiocytosis; TBB, transbronchial lung biopsy; UIP, usual interstitial pneumonitis.
INTRODUCTION Interstitial lung diseases (ILD) comprise a group of diffuse pulmonary parenchymal diseases that are classified together because of similar clinical, radiological and physiological manifestations.1 Pulmonary function tests and high-resolution computed tomography (HRCT) scanning play an important role in improving our understanding of these disease processes. However, ILD comprise a heterogeneous group of diseases with different prognostic and therapeutic implications; a definitive histological confirmation is usually required to establish the exact diagnosis.1–6 The transbronchial biopsy using forceps (forcepsTBB) usually obtain representative lung tissue from peri-bronchial and centrilobular regions. The monomorphous histological patterns (cryptogenic organizing pneumonia (COP)), eosinophilic pneumonia and diffuse alveolar damage are identifiable in small lung fragments. However, the pathological specimens obtained by TBB may not be sufficient to define the histological pattern in usual interstitial pneumonitis/idiopathic pulmonary fibrosis (UIP/ IPF), desquamative interstitial pneumonia (DIP) and nonspecific interstitial pneumonitis (NSIP). Due to these inherent limitations of forceps-TBB, there is a debate in the literature whether TBB could become the diagnostic modality of choice in patients with undiagnosed ILD.7–12 Given the relatively small Respirology (2014) 19, 683–688 doi: 10.1111/resp.12296
684 size of lung tissue samples obtained via conventional forceps-TBB, many guidelines mandate the use of open lung biopsy (OLB) to establish the histological diagnosis of ILD.13–16 Although surgical lung biopsy is considered the gold standard, the procedure requires general anaesthesia, and mandates hospitalization with a chest tube in place. Moreover, some reports have shown that this surgical procedure may be associated with increased mortality in IPF.17 Cryotherapy has been used in bronchoscopy for several years. Its main use is in the excision of endobronchial lesions, in patients of bronchial obstruction.18–20 Cryosurgical equipment operates by the Joule–Thomson effect, which dictates that a compressed gas released at high flow rapidly expands and creates a very low temperature at the tip of the flexible probe that is introduced through the working channel of the bronchoscope. The advantage of the cryoprobe is that large pieces of tissue can be extracted by cryoadhesion. It may increase the diagnostic yield of cryotransbronchial lung biopsy (cryo-TBB) in diagnosis of ILD and reduce the need for a lung biopsy.21–23 In a previous report,24 we demonstrated the efficacy and safety of cryo-TBB in lung transplantation patients performed under moderate sedation without an endotracheal tube. The aim of the current report was to explore the diagnostic yield of ambulatorybased cryo-TBB procedure in the work-up of patients presented with clinical, physiological and radiographic features of undiagnosed ILD. The contribution of the procedure to the diagnostic algorithm of ILD was assessed in order to explore the role of cryoTBB as a substitute for OLB in these patients.
METHODS A retrospective data evaluation was performed of consecutive patients referred to our institute (University-affiliated Tertiary Care medical centre) for evaluation of ILD from March 2010 to July 2012. All patients underwent a routine structured diagnostic algorithm that included: 1 Detailed history including drug and occupational exposure and complete physical examination. 2 Spirometry (with and without bronchodilator), plethysmographic lung volumes, diffusing capacity of carbon monoxide (corrected to haemoglobin) and 6-min walking test. 3 High-resolution chest computed tomography scan 4 Laboratory blood testing a complete blood count erythrocyte sedimentation rate, routine liver and renal function test including calcium level. Antinuclear antibody, rheumatoid factor, antineutrophil cytoplasmic antibody (C-, P-ANCA), antiglomerular basement membrane antibody, aldolase, creatine kinase, anti-Jo-1 antibody. All patients underwent evaluation by a team of pulmonologists and radiologists. They were referred for histological confirmation of ILD by cryo-TBB when a specific diagnosis could not be made confidently on the basis of the clinical context, the pathological process and findings on HRCT. Respirology (2014) 19, 683–688
O Fruchter et al.
The interdisciplinary team including pathologist made a final clinicopathological diagnosis of ILD: 1 Definite ILD: Clinical, radiological and histological data are all consistent with a single ILD entity. 2 Probable ILD: Clinical, radiological and histological data are suggestive of a single ILD entity or several closely related ILD although a definitive diagnosis of a single ILD cannot be made. 3 Inconclusive: Clinical, radiological and histological data obtained by cryo-TBB are not sufficient to establish diagnosis, and surgical lung biopsy is required. Written informed consent for bronchoscopy and tissue sampling was obtained from all patients. Analysis of the data was approved by the institutional review board (No: 6668).
Bronchoscopy procedure All procedures were carried out at the bronchoscopy suite. Moderate sedation was started with intravenous injection of a bolus of 2–4 mg midazolam and 0.5–1 mg alfentanil, and it was maintained with intermittent boluses of 1–3 mg intravenous midazolam or 0.5 mg intravenous alfentanil, according to clinical judgment. Oxygen saturation, blood pressure, ECG and transcutaneous carbon dioxide partial pressure were monitored continuously. Cryo-TBB procedure A flexible cryo-probe measuring 2.4 mm in diameter were used (ERBE, Tubingen, Germany). The probe was cooled with nitrous oxide that decreases the temperature in the probe’s tip to −89°C within several seconds. The pulmonary segment for biopsy was usually in the lateral or anterior basal segments of the right lower lobe, or the most affected segment according to imaging studies of the chest; 1–2 cryo biopsy samples were taken from this region. Usually an additional single cryobiopsy was taken from a region that was less affected by the disease according to imaging. The bronchoscope (Olympus 1T180; Olympus, Tokyo Japan) was introduced nasally and the selected bronchus intubated. The cryoprobe was introduced through the working channel under fluoroscopic guidance. A distance of approximately 1–2 cm from the thoracic wall was considered optimal. The probe was cooled for approximately 4 sec, and then the entire bronchoscope was retracted with the frozen lung tissue being attached on the probe’s tip. The frozen specimen was thawed in saline and fixed in 4% formalin. Within 2 h after the procedure, a chest X-ray was performed to exclude pneumothorax and the patients were discharged. Processing the histological samples Specimens were embedded in paraffin and stained with HE, elastica van Gieson and periodic acid–Schiff. Each slide was evaluated by a single lung pathologist who is aware of the clinical and the radiological features. HE slides were scanned by a Midi Slide scanning system using the Mirax Viewer Image Software (Carl Zeiss MicroImaging, Göttingen, Germany). The © 2014 Asian Pacific Society of Respirology
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total area of the biopsy specimens and the area of the alveolar part were measured and expressed in μm2. The pathological report included the surface area of the biopsy in mm2; (the entire amount of biopsy material was calculated) and the percentage of alveolated versus bronchial tissue.23
Statistical analysis Data were analysed using SPSS software, v14.0 (IBM, Tel-Aviv, Israel).
RESULTS Patients A total of 75 patients (mean age 56.2, range 17–81 years) with undiagnosed ILD that underwent cryoTBB between March 2010 to July 2012 were recruited from an initial cohort of 92 patients referred to our centre for evaluation. Of the remaining 17 patients, 2 refused to undergo TBB, 1 underwent OLB as the initial diagnostic modality and in 14 patients, the clinical and imaging studies were sufficient to establish a presumptive diagnosis of IPF. The clinical characteristics of the patients are presented in Table 1. Biopsy procedures On average, three biopsy samples were taken by cryoprobe (range 2–4). The average procedural duration of cryo-TBB were 7 min (range 5–13 minutes), with a mean fluoroscopy time of 30 sec. Only three patients (4%) needed bleeding control by cold saline instillation, and two of the patients (2.6%) had small pneumothoraces which resolved spontaneously. No clinical significant exacerbation of the underlying lung pathology was observed. Histological results The histological results obtained by cryo-TBB are presented in Table 2. Preparation and staining were possible in all of the samples, and no crush artefacts were observed. All samples contained lung tissue. The average surface area of the samples taken by cryoTBB was 9 mm2, with a high average percentage of alveolated tissue (mean 70%). The most common
Table 1 Baseline characteristics and procedural details of patients with undiagnosed interstitial lung diseases that underwent cryo-transbronchial lung biopsy (TBB) Cryo-TBB n = 75 Age ± SD Male/female Length of procedure (min) Fluoroscopy time (sec) No. of samples (range) Significant bleeding Pneumothorax © 2014 Asian Pacific Society of Respirology
56.2 ± 16.0 (17–81) 41/34 7 min (5–13 min) 30 s (12–37 s) 3 (2–4) 3 (4%) 2 (2.6%)
pathological diagnoses were idiopathic NSIP (n = 22) interstitial fibrosis (n = 21), COP (n = 11) and UIP (n = 7) (Table 2). Representative radiological and pathological examples are presented in Figures 1–3. In two patients, histological data obtained from two lobes was inconsistent. In both patients, UIP and NSIP histology was obtained from different lobes of the same patient. These patients were pathologically classified as UIP.
Clinical and histological correlation A definite clinicopathological consensus diagnosis was possible in 52 (70%), and probable clinicopathological diagnosis was made in 21 (28%) of patients. A definite clinical-radiological-pathological diagnosis was made in all patients with COP, pulmonary Langerhans cell histiocytosis (PLCH), LAM, sarcoidosis, lipoid pneumonia, silicosis, eosinophilic pneumonia, silicosis, alveolar proteinosis, lymphangitis carcinomatosis, hypersensitivity pneumonitis and DIP, UIP and patients with NSIP. Probable clinicopathological diagnosis was made in 21 patients with interstitial fibrosis. The preoperative clinicalradiological diagnosis was defined as probable before histological confirmation in 12 patients that subsequently were definitely diagnosed as UIP (n = 2), LAM (n = 1), PLCH (n = 1), silicosis (n = 1), alveolar proteinosis (n = 1) and NSIP (n = 6). The clinical diagnosis changed from uncertain preoperatively, to definite following a clear histological diagnosis obtained by cryobiopsy, in 41 patients. In three patients, preoperative probable diagnosis of IPF-UIP changed to NSIP; in two patients, preoperative probable diagnosis Table 2 Histological results of specimens obtained from patients with undiagnosed interstitial lung diseases by cryo-TBB Cryo-TBB n = 75 Mean sample area (mm2) Alveolated tissue (%) COP NSIP PLCH LAM UIP Sarcoidosis Lipoid pneumonia Alveolar proteinosis DIP HP Silicosis Eosinophilic pneumonia Lymphangitis carcinomatosis Interstitial fibrosis Normal lung tissue
9 (6–18) 70% (55–85%) 11 21 3 1 7 1 1 1 1 1 1 1 1 22 2
COP, cryptogenic organizing pneumonia; DIP, desquamative interstitial pneumonia; HP, hypersensitivity pneumonitis; LAM, lymphangioleiomyomatosis; NSIP, nonspecific interstitial pneumonitis; PLCH, pulmonary Langerhans cell histiocytosis; TBB, transbronchial lung biopsy; UIP, usual interstitial pneumonitis. Respirology (2014) 19, 683–688
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Figure 1 Chest X-ray of a 32-year-old smoking man with bilateral dense reticulo-nodular infiltrations (a) diagnosed as pulmonary Langerhans cell histiocytosis (PLCH) by cryo-transbronchial lung biopsy (TBB) (b) showing thick alveolar septa filled by numerous macrophages containing brownish pigment and dense interstitial fibrosis with CD1a-positive Langerhans cells.
of NSIP changed to IPF-UIP, and in 1 patient, the diagnosis was unexpectedly changed from IPF-UIP to lymphangitis carcinomatosis. In only two patients (2%), normal lung tissue was obtained; the procedure was regarded as nondiagnostic, hence, no clinicopathological consensus was possible. One was diagnosed with IPF-UIP on OLB; the other refused further investigations and was classified as presumed NSIP according only to clinical and radiological features.
DISCUSSION This study describes the safety and efficacy of TBB using flexible cryoprobe in the diagnostic work-up of patients with ILD. Given the relatively small size of lung tissue samples obtained via conventional forceps-TBB, the majority of consensus guidelines mandate the use of Respirology (2014) 19, 683–688
Figure 2 High-resolution chest computed tomography scan of a 27-year-old nonsmoking female (a) with clinical and radiological features of lymphangioleiomyomatosis (LAM) proved by cryotransbronchial lung biopsy (TBB) (b) showing thin-walled cysts with proliferation of spindle-like cells positive for HMB-45 and SMA antigen (LAM cells).
OLB to establish a definite histological diagnosis of ILD.13–16 The median mortality is 4–6% within 30 days following surgical lung biopsy for UIP but OLB performed at the time of acute exacerbation of IPF resulted in very high 30-day mortality rates of up to 30%.15–17 Cryo-TBB was shown to be safe and feasible; representative lung tissue could be obtained in the vast majority of patients. The average duration of the procedure and the total fluoroscopy time were short, and the rate of complications was low. In many patients with ILD, tissue sampling may be crucial to establish a diagnosis.1–6 TBB may provide diagnostic material; however, its use is limited by the small size of lung tissue samples obtained particular when expecting NSIP, IPF, LAM and PLCH.7–12 A major © 2014 Asian Pacific Society of Respirology
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(b)
was low (less than 5%); however, the diagnostic yield was unsatisfactory because in 50% of patients, the pathological results were inconclusive or nondiagnostic. Griff et al.23 examined the efficacy of cryo-TBB in 15 patients with high rate of success in diagnosis of diffuse lung diseases (in particular lung infiltrations and not ILD) and low rate of complications. Kropski et al.24 examined the use of cryo-TBB in 25 patients and found that in patients with suspected diffuse parenchymal lung disease, bronchoscopic cryobiopsy is a promising and minimally invasive approach to obtain lung tissue with high diagnostic yield. In all studies, the size of the specimen obtained by cryoTBB was considerably larger than that obtained by traditional forceps. Our study is the largest case series of cryo-TBB in patients with diffuse lung diseases to date. In addition, in contrast to previous reports, we are performing cryo-TBB under moderate sedation, without an endotracheal tube and on an ambulatory basis.25 Some centres advocate the use of endotracheal tube during cryo-TBB to avoid upper airway trauma and to allow easier control of bleeding. We demonstrate that when cryo-TBB is performed by an experienced endoscopist, the procedure can be safely completed without endotracheal tube. The major limitation of the current report is its retrospective nature. Additional prospective randomized trials are required before cryo-TBB becomes the gold standard procedure for diagnosis of ILD. The technique described in the current report represents a major advantage over the traditional technique of forceps-TBB and is likely to replace OLB in the majority of patients.
REFERENCES Figure 3 High-resolution chest computed tomography (CT) scan of a 77-year-old man showing severe bilateral subpleural fibrotic changes confirmed as usual interstitial pneumonitis (UIP) by cryo-transbronchial lung biopsy (TBB) (b) demonstrating patchy interstitial fibrosis with fibrotic foci of fibroblast proliferation and honeycomb changes with distorted air spaces and smooth muscle hyperplasia.
advantage of cryo-TBB technique is that the sample is frozen, hence obtaining a large sample with a high percentage of alveolated tissue without no crush artefacts. Only four previous studies have evaluated the clinical advantages of transbronchial cryo biopsies in patients with diffuse lung diseases.21–24 Babiak et al.21 examined the efficacy of cryo-TBB in 41 patients with diffuse lung diseases and concluded that it contributed to a definitive diagnosis in a substantial number of patients (10/41). The rate of complications was very low and similar to our report (less than 5%). Pajares et al.22 described their experience in cryo-TBB for the diagnosis of ILD in 10 patients. Similar to previous reports, the rate of complication © 2014 Asian Pacific Society of Respirology
1 King TE Jr. Clinical advances in the diagnosis and therapy of the interstitial lung diseases. Am. J. Respir. Crit. Care Med. 2005; 172: 268–79. 2 Travis WD, Costabel U, Hansell DM, King TE Jr, Lynch DA, Nicholson AG, Ryerson CJ, Ryu JH, Selman M, Wells AU et al. An official American Thoracic Society/European Respiratory Society statement: update of the international multidisciplinary classification of the idiopathic interstitial pneumonias. Am. J. Respir. Crit. Care Med. 2013; 188: 733–48. 3 Ryu JH, Daniels CE, Hartman TE, Yi ES. Diagnosis of interstitial lung diseases. Mayo Clin. Proc. 2007; 82: 976–86. 4 Larsen BT, Colby TV. Update for pathologists on idiopathic interstitial pneumonias. Arch. Pathol. Lab. Med. 2012; 136: 1234–41. Review. 5 Fishbein MC. Diagnosis: to biopsy or not to biopsy: assessing the role of surgical lung biopsy in the diagnosis of idiopathic pulmonary fibrosis. Chest 2005; 128: 520S–525S. 6 Wells AU. Managing diagnostic procedures in idiopathic pulmonary fibrosis. Eur. Respir. Rev. 2013; 22: 158–62. 7 Margaritopoulos GA, Wells AU. The role of transbronchial biopsy in the diagnosis of diffuse parenchymal lung diseases: con. Rev. Port. Pneumol. 2012; 18: 61–3. 8 Casoni GL, Cordeiro CR Jr, Tomassetti S, Romagnoli M, Chilosi M, Cancellieri A, Gurioli C, Poletti V. The role of transbronchial biopsy in the diagnosis of diffuse parenchymal lung diseases: pro. Rev. Port. Pneumol. 2012; 18: 57–60. Respirology (2014) 19, 683–688
688 9 Verbeken EK. Classifying interstitial lung diseases in a fractal lung: a morphologist’s view ‘anno Domini 2000’. Eur. Respir. J. Suppl. 2001; 32: 107 s–113 s. 10 Tomassetti S, Cavazza A, Colby TV, Ryu JH, Nanni O, Scarpi E, Tantalocco P, Buccioli M, Dubini A, Piciucchi S et al. Transbronchial biopsy is useful in predicting UIP pattern. Respir. Res. 2012; 13: 96. 11 Oliveira CC, Fabro AT, Ribeiro SM, Defaveri J, Capelozzi VL, Queluz TH, Yoo HH. Evaluation of the use of transbronchial biopsy in patients with clinical suspicion of interstitial lung disease. J. Bras. Pneumol. 2011; 37: 168–75. 12 Leslie KO, Gruden JF, Parish JM, Scholand MB. Transbronchial biopsy interpretation in the patient with diffuse parenchymal lung disease. Arch. Pathol. Lab. Med. 2007; 131: 407–23. Review. 13 Blackhall V, Asif M, Renieri A, Civitelli S, Kirk A, Jilaihawi A, Granato F. The role of surgical lung biopsy in the management of interstitial lung disease: experience from a single institution in the UK. Interact. Cardiovasc. Thorac. Surg. 2013; 17: 253–7. 14 Lee YC, Wu CT, Hsu HH, Huang PM, Chang YL. Surgical lung biopsy for diffuse pulmonary disease: experience of 196 patients. J. Thorac. Cardiovasc. Surg. 2005; 129: 984–90. 15 Sigurdsson MI, Isaksson HJ, Gudmundsson G, Gudbjartsson T. Diagnostic surgical lung biopsies for suspected interstitial lung diseases: a retrospective study. Ann. Thorac. Surg. 2009; 88: 227– 32. 16 Nguyen W, Meyer KC. Surgical lung biopsy for the diagnosis of interstitial lung disease: a review of the literature and recommendations for optimizing safety and efficacy. Sarcoidosis. Vasc. Diffuse Lung Dis. 2013; 30: 3–16.
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O Fruchter et al. 17 Kondoh Y, Taniguchi H, Kitaichi M, Yokoi T, Johkoh T, Oishi T, Kimura T, Nishiyama O, Kato K, du Bois RM. Acute exacerbation of interstitial pneumonia following surgical lung biopsy. Respir. Med. 2006; 100: 1753–9. 18 Schumann C, Hetzel J, Babiak AJ, Merk T, Wibmer T, Möller P, Lepper PM, Hetzel M. Cryoprobe biopsy increases the diagnostic yield in endobronchial tumor lesions. Thorac. Cardiovasc. Surg. 2010; 140: 417–21. 19 Aktas Z, Gunay E, Hoca NT, Yilmaz A, Demirag F, Gunay S, Sipit T, Kurt EB. Endobronchial cryobiopsy or forceps biopsy for lung cancer diagnosis. Ann. Thorac. Med. 2010; 5: 242–6. 20 Hetzel J, Eberhardt R, Herth FJ, Petermann C, Reichle G, Freitag L, Dobbertin I, Franke KJ, Stanzel F, Beyer T et al. Cryobiopsy increases the diagnostic yield of endobronchial biopsy: a multicentre trial. Eur. Respir. J. 2012; 39: 685–90. 21 Babiak A, Hetzel J, Krishna G, Fritz P, Moeller P, Balli T, Hetzel M. Transbronchial cryobiopsy: a new tool for lung biopsies. Respiration 2009; 78: 203–8. 22 Pajares V, Torrego A, Puzo C, Lerma E, Gil De Bernabé MA, Franquet T. Transbronchial lung biopsy using cryoprobes. Arch. Bronconeumol. 2010; 46: 111–15. 23 Griff S, Ammenwerth W, Schönfeld N, Bauer TT, Mairinger T, Blum TG, Kollmeier J, Grüning W. Morphometrical analysis of transbronchial cryobiopsies. Diagn. Pathol. 2011; 16: 53. 24 Kropski JA, Pritchett JM, Mason WR, Sivarajan L, Gleaves LA. Bronchoscopic cryobiopsy for the diagnosis of diffuse parenchymal lung disease. PLoS ONE 2013 8; 11: e78674. 25 Fruchter O, Fridel L, Rosengarten D, Raviv Y, Rosanov V, Kramer MR. Transbronchial cryo-biopsy in lung transplantation patients: first report. Respirology 2013; 18: 669–73.
© 2014 Asian Pacific Society of Respirology
ORIGINAL ARTICLE
Histological diagnosis of interstitial lung diseases by cryo-transbronchial biopsy OREN FRUCHTER,1,3 LUDMILA FRIDEL,2 BAYYA ABED EL RAOUF,1 NADER ABDEL-RAHMAN,1 DROR ROSENGARTEN1 AND MORDECHAI R. KRAMER1,3 1
Institute of Pulmonary, and 2Department of Pathology, Rabin Medical Center, Petah Tiqwa, and 3The Sackler School of Medicine, Tel-Aviv University, Tel Aviv, Israel
ABSTRACT Background and objective: The gold standard for the histological diagnosis of interstitial lung diseases (ILD) is an open lung biopsy (OLB). Tissue samples obtained by forceps transbronchial lung biopsies (TBB) are usually too small. We aim to evaluate the efficacy and safety of cryo-TBB for the diagnosis of ILD and to explore its role as substitute for OLB. Methods: Seventy-five patients (mean age 56.2 years) with clinical and radiological features suggestive of ILD underwent cryo-TBB under moderate sedation. The diagnostic contribution on the work-up of suspected ILD was assessed. Results: No major complications occurred during cryo-TBB procedures. The mean cross-sectional area of the biopsy specimen obtained was 9 mm2 with an average of 70% alveolated tissue. The most common pathological diagnoses were idiopathic nonspecific interstitial pneumonitis (n = 22), cryptogenic organizing pneumonia (n = 11) and usual interstitial pneumonitis (n = 7). There were three patients of pulmonary Langerhans cell histiocytosis and one patient of pulmonary lymphangioleiomyomatosis. A definite and probable clinicopathological consensus diagnosis was possible in 70% and 28% of patients, respectively. In only 2% of patients’ diagnosis could not be established. Conclusions: Cryo-TBB is a safe and effective minimally invasive modality for the diagnosis of ILD. No OLB is needed in the majority of patients. Key words: alveolar proteinosis, bronchoscopy and interventional techniques, interstitial lung disease, nonspecific interstitial pneumonitis, usual interstitial pneumonitis. Abbreviations: COP, cryptogenic organizing pneumonia; DIP, desquamative interstitial pneumonia; HRCT, high-resolution computed tomography; ILD, interstitial lung diseases; IPF, idiopathic pulmonary fibrosis; LAM, lymphangioleiomyomatosis; Correspondence: Oren Fruchter, Interventional Bronchoscopy, The Pulmonary Division, Rabin Medical Center, Beilinson Hospital, Petach Tikva 49100, Israel. Email: [email protected] Received 17 December 2013; invited to revise 29 January and 21 February 2014; revised 30 January and 23 February 2014; accepted 23 February 2013 (Associate Editor: Toby Maher). Article first published online: 20 April 2014 © 2014 Asian Pacific Society of Respirology
SUMMARY AT A GLANCE Cryo-transbronchial biopsy provides diagnostic material that enables a histological diagnosis in patients with interstitial lung diseases and obviates the need for open lung biopsy in the majority of patients.
NSIP, nonspecific interstitial pneumonitis; OLB, open lung biopsy; PLCH, pulmonary Langerhans cell histiocytosis; TBB, transbronchial lung biopsy; UIP, usual interstitial pneumonitis.
INTRODUCTION Interstitial lung diseases (ILD) comprise a group of diffuse pulmonary parenchymal diseases that are classified together because of similar clinical, radiological and physiological manifestations.1 Pulmonary function tests and high-resolution computed tomography (HRCT) scanning play an important role in improving our understanding of these disease processes. However, ILD comprise a heterogeneous group of diseases with different prognostic and therapeutic implications; a definitive histological confirmation is usually required to establish the exact diagnosis.1–6 The transbronchial biopsy using forceps (forcepsTBB) usually obtain representative lung tissue from peri-bronchial and centrilobular regions. The monomorphous histological patterns (cryptogenic organizing pneumonia (COP)), eosinophilic pneumonia and diffuse alveolar damage are identifiable in small lung fragments. However, the pathological specimens obtained by TBB may not be sufficient to define the histological pattern in usual interstitial pneumonitis/idiopathic pulmonary fibrosis (UIP/ IPF), desquamative interstitial pneumonia (DIP) and nonspecific interstitial pneumonitis (NSIP). Due to these inherent limitations of forceps-TBB, there is a debate in the literature whether TBB could become the diagnostic modality of choice in patients with undiagnosed ILD.7–12 Given the relatively small Respirology (2014) 19, 683–688 doi: 10.1111/resp.12296
684 size of lung tissue samples obtained via conventional forceps-TBB, many guidelines mandate the use of open lung biopsy (OLB) to establish the histological diagnosis of ILD.13–16 Although surgical lung biopsy is considered the gold standard, the procedure requires general anaesthesia, and mandates hospitalization with a chest tube in place. Moreover, some reports have shown that this surgical procedure may be associated with increased mortality in IPF.17 Cryotherapy has been used in bronchoscopy for several years. Its main use is in the excision of endobronchial lesions, in patients of bronchial obstruction.18–20 Cryosurgical equipment operates by the Joule–Thomson effect, which dictates that a compressed gas released at high flow rapidly expands and creates a very low temperature at the tip of the flexible probe that is introduced through the working channel of the bronchoscope. The advantage of the cryoprobe is that large pieces of tissue can be extracted by cryoadhesion. It may increase the diagnostic yield of cryotransbronchial lung biopsy (cryo-TBB) in diagnosis of ILD and reduce the need for a lung biopsy.21–23 In a previous report,24 we demonstrated the efficacy and safety of cryo-TBB in lung transplantation patients performed under moderate sedation without an endotracheal tube. The aim of the current report was to explore the diagnostic yield of ambulatorybased cryo-TBB procedure in the work-up of patients presented with clinical, physiological and radiographic features of undiagnosed ILD. The contribution of the procedure to the diagnostic algorithm of ILD was assessed in order to explore the role of cryoTBB as a substitute for OLB in these patients.
METHODS A retrospective data evaluation was performed of consecutive patients referred to our institute (University-affiliated Tertiary Care medical centre) for evaluation of ILD from March 2010 to July 2012. All patients underwent a routine structured diagnostic algorithm that included: 1 Detailed history including drug and occupational exposure and complete physical examination. 2 Spirometry (with and without bronchodilator), plethysmographic lung volumes, diffusing capacity of carbon monoxide (corrected to haemoglobin) and 6-min walking test. 3 High-resolution chest computed tomography scan 4 Laboratory blood testing a complete blood count erythrocyte sedimentation rate, routine liver and renal function test including calcium level. Antinuclear antibody, rheumatoid factor, antineutrophil cytoplasmic antibody (C-, P-ANCA), antiglomerular basement membrane antibody, aldolase, creatine kinase, anti-Jo-1 antibody. All patients underwent evaluation by a team of pulmonologists and radiologists. They were referred for histological confirmation of ILD by cryo-TBB when a specific diagnosis could not be made confidently on the basis of the clinical context, the pathological process and findings on HRCT. Respirology (2014) 19, 683–688
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The interdisciplinary team including pathologist made a final clinicopathological diagnosis of ILD: 1 Definite ILD: Clinical, radiological and histological data are all consistent with a single ILD entity. 2 Probable ILD: Clinical, radiological and histological data are suggestive of a single ILD entity or several closely related ILD although a definitive diagnosis of a single ILD cannot be made. 3 Inconclusive: Clinical, radiological and histological data obtained by cryo-TBB are not sufficient to establish diagnosis, and surgical lung biopsy is required. Written informed consent for bronchoscopy and tissue sampling was obtained from all patients. Analysis of the data was approved by the institutional review board (No: 6668).
Bronchoscopy procedure All procedures were carried out at the bronchoscopy suite. Moderate sedation was started with intravenous injection of a bolus of 2–4 mg midazolam and 0.5–1 mg alfentanil, and it was maintained with intermittent boluses of 1–3 mg intravenous midazolam or 0.5 mg intravenous alfentanil, according to clinical judgment. Oxygen saturation, blood pressure, ECG and transcutaneous carbon dioxide partial pressure were monitored continuously. Cryo-TBB procedure A flexible cryo-probe measuring 2.4 mm in diameter were used (ERBE, Tubingen, Germany). The probe was cooled with nitrous oxide that decreases the temperature in the probe’s tip to −89°C within several seconds. The pulmonary segment for biopsy was usually in the lateral or anterior basal segments of the right lower lobe, or the most affected segment according to imaging studies of the chest; 1–2 cryo biopsy samples were taken from this region. Usually an additional single cryobiopsy was taken from a region that was less affected by the disease according to imaging. The bronchoscope (Olympus 1T180; Olympus, Tokyo Japan) was introduced nasally and the selected bronchus intubated. The cryoprobe was introduced through the working channel under fluoroscopic guidance. A distance of approximately 1–2 cm from the thoracic wall was considered optimal. The probe was cooled for approximately 4 sec, and then the entire bronchoscope was retracted with the frozen lung tissue being attached on the probe’s tip. The frozen specimen was thawed in saline and fixed in 4% formalin. Within 2 h after the procedure, a chest X-ray was performed to exclude pneumothorax and the patients were discharged. Processing the histological samples Specimens were embedded in paraffin and stained with HE, elastica van Gieson and periodic acid–Schiff. Each slide was evaluated by a single lung pathologist who is aware of the clinical and the radiological features. HE slides were scanned by a Midi Slide scanning system using the Mirax Viewer Image Software (Carl Zeiss MicroImaging, Göttingen, Germany). The © 2014 Asian Pacific Society of Respirology
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total area of the biopsy specimens and the area of the alveolar part were measured and expressed in μm2. The pathological report included the surface area of the biopsy in mm2; (the entire amount of biopsy material was calculated) and the percentage of alveolated versus bronchial tissue.23
Statistical analysis Data were analysed using SPSS software, v14.0 (IBM, Tel-Aviv, Israel).
RESULTS Patients A total of 75 patients (mean age 56.2, range 17–81 years) with undiagnosed ILD that underwent cryoTBB between March 2010 to July 2012 were recruited from an initial cohort of 92 patients referred to our centre for evaluation. Of the remaining 17 patients, 2 refused to undergo TBB, 1 underwent OLB as the initial diagnostic modality and in 14 patients, the clinical and imaging studies were sufficient to establish a presumptive diagnosis of IPF. The clinical characteristics of the patients are presented in Table 1. Biopsy procedures On average, three biopsy samples were taken by cryoprobe (range 2–4). The average procedural duration of cryo-TBB were 7 min (range 5–13 minutes), with a mean fluoroscopy time of 30 sec. Only three patients (4%) needed bleeding control by cold saline instillation, and two of the patients (2.6%) had small pneumothoraces which resolved spontaneously. No clinical significant exacerbation of the underlying lung pathology was observed. Histological results The histological results obtained by cryo-TBB are presented in Table 2. Preparation and staining were possible in all of the samples, and no crush artefacts were observed. All samples contained lung tissue. The average surface area of the samples taken by cryoTBB was 9 mm2, with a high average percentage of alveolated tissue (mean 70%). The most common
Table 1 Baseline characteristics and procedural details of patients with undiagnosed interstitial lung diseases that underwent cryo-transbronchial lung biopsy (TBB) Cryo-TBB n = 75 Age ± SD Male/female Length of procedure (min) Fluoroscopy time (sec) No. of samples (range) Significant bleeding Pneumothorax © 2014 Asian Pacific Society of Respirology
56.2 ± 16.0 (17–81) 41/34 7 min (5–13 min) 30 s (12–37 s) 3 (2–4) 3 (4%) 2 (2.6%)
pathological diagnoses were idiopathic NSIP (n = 22) interstitial fibrosis (n = 21), COP (n = 11) and UIP (n = 7) (Table 2). Representative radiological and pathological examples are presented in Figures 1–3. In two patients, histological data obtained from two lobes was inconsistent. In both patients, UIP and NSIP histology was obtained from different lobes of the same patient. These patients were pathologically classified as UIP.
Clinical and histological correlation A definite clinicopathological consensus diagnosis was possible in 52 (70%), and probable clinicopathological diagnosis was made in 21 (28%) of patients. A definite clinical-radiological-pathological diagnosis was made in all patients with COP, pulmonary Langerhans cell histiocytosis (PLCH), LAM, sarcoidosis, lipoid pneumonia, silicosis, eosinophilic pneumonia, silicosis, alveolar proteinosis, lymphangitis carcinomatosis, hypersensitivity pneumonitis and DIP, UIP and patients with NSIP. Probable clinicopathological diagnosis was made in 21 patients with interstitial fibrosis. The preoperative clinicalradiological diagnosis was defined as probable before histological confirmation in 12 patients that subsequently were definitely diagnosed as UIP (n = 2), LAM (n = 1), PLCH (n = 1), silicosis (n = 1), alveolar proteinosis (n = 1) and NSIP (n = 6). The clinical diagnosis changed from uncertain preoperatively, to definite following a clear histological diagnosis obtained by cryobiopsy, in 41 patients. In three patients, preoperative probable diagnosis of IPF-UIP changed to NSIP; in two patients, preoperative probable diagnosis Table 2 Histological results of specimens obtained from patients with undiagnosed interstitial lung diseases by cryo-TBB Cryo-TBB n = 75 Mean sample area (mm2) Alveolated tissue (%) COP NSIP PLCH LAM UIP Sarcoidosis Lipoid pneumonia Alveolar proteinosis DIP HP Silicosis Eosinophilic pneumonia Lymphangitis carcinomatosis Interstitial fibrosis Normal lung tissue
9 (6–18) 70% (55–85%) 11 21 3 1 7 1 1 1 1 1 1 1 1 22 2
COP, cryptogenic organizing pneumonia; DIP, desquamative interstitial pneumonia; HP, hypersensitivity pneumonitis; LAM, lymphangioleiomyomatosis; NSIP, nonspecific interstitial pneumonitis; PLCH, pulmonary Langerhans cell histiocytosis; TBB, transbronchial lung biopsy; UIP, usual interstitial pneumonitis. Respirology (2014) 19, 683–688
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Figure 1 Chest X-ray of a 32-year-old smoking man with bilateral dense reticulo-nodular infiltrations (a) diagnosed as pulmonary Langerhans cell histiocytosis (PLCH) by cryo-transbronchial lung biopsy (TBB) (b) showing thick alveolar septa filled by numerous macrophages containing brownish pigment and dense interstitial fibrosis with CD1a-positive Langerhans cells.
of NSIP changed to IPF-UIP, and in 1 patient, the diagnosis was unexpectedly changed from IPF-UIP to lymphangitis carcinomatosis. In only two patients (2%), normal lung tissue was obtained; the procedure was regarded as nondiagnostic, hence, no clinicopathological consensus was possible. One was diagnosed with IPF-UIP on OLB; the other refused further investigations and was classified as presumed NSIP according only to clinical and radiological features.
DISCUSSION This study describes the safety and efficacy of TBB using flexible cryoprobe in the diagnostic work-up of patients with ILD. Given the relatively small size of lung tissue samples obtained via conventional forceps-TBB, the majority of consensus guidelines mandate the use of Respirology (2014) 19, 683–688
Figure 2 High-resolution chest computed tomography scan of a 27-year-old nonsmoking female (a) with clinical and radiological features of lymphangioleiomyomatosis (LAM) proved by cryotransbronchial lung biopsy (TBB) (b) showing thin-walled cysts with proliferation of spindle-like cells positive for HMB-45 and SMA antigen (LAM cells).
OLB to establish a definite histological diagnosis of ILD.13–16 The median mortality is 4–6% within 30 days following surgical lung biopsy for UIP but OLB performed at the time of acute exacerbation of IPF resulted in very high 30-day mortality rates of up to 30%.15–17 Cryo-TBB was shown to be safe and feasible; representative lung tissue could be obtained in the vast majority of patients. The average duration of the procedure and the total fluoroscopy time were short, and the rate of complications was low. In many patients with ILD, tissue sampling may be crucial to establish a diagnosis.1–6 TBB may provide diagnostic material; however, its use is limited by the small size of lung tissue samples obtained particular when expecting NSIP, IPF, LAM and PLCH.7–12 A major © 2014 Asian Pacific Society of Respirology
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was low (less than 5%); however, the diagnostic yield was unsatisfactory because in 50% of patients, the pathological results were inconclusive or nondiagnostic. Griff et al.23 examined the efficacy of cryo-TBB in 15 patients with high rate of success in diagnosis of diffuse lung diseases (in particular lung infiltrations and not ILD) and low rate of complications. Kropski et al.24 examined the use of cryo-TBB in 25 patients and found that in patients with suspected diffuse parenchymal lung disease, bronchoscopic cryobiopsy is a promising and minimally invasive approach to obtain lung tissue with high diagnostic yield. In all studies, the size of the specimen obtained by cryoTBB was considerably larger than that obtained by traditional forceps. Our study is the largest case series of cryo-TBB in patients with diffuse lung diseases to date. In addition, in contrast to previous reports, we are performing cryo-TBB under moderate sedation, without an endotracheal tube and on an ambulatory basis.25 Some centres advocate the use of endotracheal tube during cryo-TBB to avoid upper airway trauma and to allow easier control of bleeding. We demonstrate that when cryo-TBB is performed by an experienced endoscopist, the procedure can be safely completed without endotracheal tube. The major limitation of the current report is its retrospective nature. Additional prospective randomized trials are required before cryo-TBB becomes the gold standard procedure for diagnosis of ILD. The technique described in the current report represents a major advantage over the traditional technique of forceps-TBB and is likely to replace OLB in the majority of patients.
REFERENCES Figure 3 High-resolution chest computed tomography (CT) scan of a 77-year-old man showing severe bilateral subpleural fibrotic changes confirmed as usual interstitial pneumonitis (UIP) by cryo-transbronchial lung biopsy (TBB) (b) demonstrating patchy interstitial fibrosis with fibrotic foci of fibroblast proliferation and honeycomb changes with distorted air spaces and smooth muscle hyperplasia.
advantage of cryo-TBB technique is that the sample is frozen, hence obtaining a large sample with a high percentage of alveolated tissue without no crush artefacts. Only four previous studies have evaluated the clinical advantages of transbronchial cryo biopsies in patients with diffuse lung diseases.21–24 Babiak et al.21 examined the efficacy of cryo-TBB in 41 patients with diffuse lung diseases and concluded that it contributed to a definitive diagnosis in a substantial number of patients (10/41). The rate of complications was very low and similar to our report (less than 5%). Pajares et al.22 described their experience in cryo-TBB for the diagnosis of ILD in 10 patients. Similar to previous reports, the rate of complication © 2014 Asian Pacific Society of Respirology
1 King TE Jr. Clinical advances in the diagnosis and therapy of the interstitial lung diseases. Am. J. Respir. Crit. Care Med. 2005; 172: 268–79. 2 Travis WD, Costabel U, Hansell DM, King TE Jr, Lynch DA, Nicholson AG, Ryerson CJ, Ryu JH, Selman M, Wells AU et al. An official American Thoracic Society/European Respiratory Society statement: update of the international multidisciplinary classification of the idiopathic interstitial pneumonias. Am. J. Respir. Crit. Care Med. 2013; 188: 733–48. 3 Ryu JH, Daniels CE, Hartman TE, Yi ES. Diagnosis of interstitial lung diseases. Mayo Clin. Proc. 2007; 82: 976–86. 4 Larsen BT, Colby TV. Update for pathologists on idiopathic interstitial pneumonias. Arch. Pathol. Lab. Med. 2012; 136: 1234–41. Review. 5 Fishbein MC. Diagnosis: to biopsy or not to biopsy: assessing the role of surgical lung biopsy in the diagnosis of idiopathic pulmonary fibrosis. Chest 2005; 128: 520S–525S. 6 Wells AU. Managing diagnostic procedures in idiopathic pulmonary fibrosis. Eur. Respir. Rev. 2013; 22: 158–62. 7 Margaritopoulos GA, Wells AU. The role of transbronchial biopsy in the diagnosis of diffuse parenchymal lung diseases: con. Rev. Port. Pneumol. 2012; 18: 61–3. 8 Casoni GL, Cordeiro CR Jr, Tomassetti S, Romagnoli M, Chilosi M, Cancellieri A, Gurioli C, Poletti V. The role of transbronchial biopsy in the diagnosis of diffuse parenchymal lung diseases: pro. Rev. Port. Pneumol. 2012; 18: 57–60. Respirology (2014) 19, 683–688
688 9 Verbeken EK. Classifying interstitial lung diseases in a fractal lung: a morphologist’s view ‘anno Domini 2000’. Eur. Respir. J. Suppl. 2001; 32: 107 s–113 s. 10 Tomassetti S, Cavazza A, Colby TV, Ryu JH, Nanni O, Scarpi E, Tantalocco P, Buccioli M, Dubini A, Piciucchi S et al. Transbronchial biopsy is useful in predicting UIP pattern. Respir. Res. 2012; 13: 96. 11 Oliveira CC, Fabro AT, Ribeiro SM, Defaveri J, Capelozzi VL, Queluz TH, Yoo HH. Evaluation of the use of transbronchial biopsy in patients with clinical suspicion of interstitial lung disease. J. Bras. Pneumol. 2011; 37: 168–75. 12 Leslie KO, Gruden JF, Parish JM, Scholand MB. Transbronchial biopsy interpretation in the patient with diffuse parenchymal lung disease. Arch. Pathol. Lab. Med. 2007; 131: 407–23. Review. 13 Blackhall V, Asif M, Renieri A, Civitelli S, Kirk A, Jilaihawi A, Granato F. The role of surgical lung biopsy in the management of interstitial lung disease: experience from a single institution in the UK. Interact. Cardiovasc. Thorac. Surg. 2013; 17: 253–7. 14 Lee YC, Wu CT, Hsu HH, Huang PM, Chang YL. Surgical lung biopsy for diffuse pulmonary disease: experience of 196 patients. J. Thorac. Cardiovasc. Surg. 2005; 129: 984–90. 15 Sigurdsson MI, Isaksson HJ, Gudmundsson G, Gudbjartsson T. Diagnostic surgical lung biopsies for suspected interstitial lung diseases: a retrospective study. Ann. Thorac. Surg. 2009; 88: 227– 32. 16 Nguyen W, Meyer KC. Surgical lung biopsy for the diagnosis of interstitial lung disease: a review of the literature and recommendations for optimizing safety and efficacy. Sarcoidosis. Vasc. Diffuse Lung Dis. 2013; 30: 3–16.
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O Fruchter et al. 17 Kondoh Y, Taniguchi H, Kitaichi M, Yokoi T, Johkoh T, Oishi T, Kimura T, Nishiyama O, Kato K, du Bois RM. Acute exacerbation of interstitial pneumonia following surgical lung biopsy. Respir. Med. 2006; 100: 1753–9. 18 Schumann C, Hetzel J, Babiak AJ, Merk T, Wibmer T, Möller P, Lepper PM, Hetzel M. Cryoprobe biopsy increases the diagnostic yield in endobronchial tumor lesions. Thorac. Cardiovasc. Surg. 2010; 140: 417–21. 19 Aktas Z, Gunay E, Hoca NT, Yilmaz A, Demirag F, Gunay S, Sipit T, Kurt EB. Endobronchial cryobiopsy or forceps biopsy for lung cancer diagnosis. Ann. Thorac. Med. 2010; 5: 242–6. 20 Hetzel J, Eberhardt R, Herth FJ, Petermann C, Reichle G, Freitag L, Dobbertin I, Franke KJ, Stanzel F, Beyer T et al. Cryobiopsy increases the diagnostic yield of endobronchial biopsy: a multicentre trial. Eur. Respir. J. 2012; 39: 685–90. 21 Babiak A, Hetzel J, Krishna G, Fritz P, Moeller P, Balli T, Hetzel M. Transbronchial cryobiopsy: a new tool for lung biopsies. Respiration 2009; 78: 203–8. 22 Pajares V, Torrego A, Puzo C, Lerma E, Gil De Bernabé MA, Franquet T. Transbronchial lung biopsy using cryoprobes. Arch. Bronconeumol. 2010; 46: 111–15. 23 Griff S, Ammenwerth W, Schönfeld N, Bauer TT, Mairinger T, Blum TG, Kollmeier J, Grüning W. Morphometrical analysis of transbronchial cryobiopsies. Diagn. Pathol. 2011; 16: 53. 24 Kropski JA, Pritchett JM, Mason WR, Sivarajan L, Gleaves LA. Bronchoscopic cryobiopsy for the diagnosis of diffuse parenchymal lung disease. PLoS ONE 2013 8; 11: e78674. 25 Fruchter O, Fridel L, Rosengarten D, Raviv Y, Rosanov V, Kramer MR. Transbronchial cryo-biopsy in lung transplantation patients: first report. Respirology 2013; 18: 669–73.
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