| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Mayo Clinic College of Medicine, Mayo Medical Center, Rochester, MN, USA.
CORRESPONDENCE: U. B. S. Prakash, Pulmonary and Critical Care Division, East-18, Mayo Building, Mayo Medical Center, Rochester, MN 55905, USA. Fax: 1 5072664372. E-mail: prakash.udaya{at}mayo.edu
Keywords: Bronchoscopic lung biopsy, bronchoscopy, diffuse lung disease, interstitial lung disease, transbronchial biopsy, transbronchoscopic biopsy
Received: January 27, 2006
Accepted July 26, 2006
 |
ABSTRACT |
|---|
 TOP ABSTRACT METHODSRESULTSDISCUSSIONREFERENCES |
|---|
The study was a retrospective analysis of patients who underwent fluoroscopy-guided BLB over a 2-yr period. Patients whose biopsy was of a lung mass or single dominant lung nodule were excluded. The usefulness of BLB was assessed to determine whether the results affected the clinical management of these patients.
During the study period, 603 patients underwent 651 BLB procedures. The results of BLB were clinically helpful in 494 (75.9%) out of 651 procedures. No diagnostic abnormality was identified in 107 (16.4%) out of the 651 biopsy procedures. This finding was clinically helpful in 59 (55.1%) out of 107 procedures, as the results excluded specific processes suspected before BLB. In 52 procedures (8% of all BLB), no lung parenchyma was obtained.
In conclusion, bronchoscopic lung biopsy is a clinically useful test in 
75% of procedures. In the 25% of bronchoscopic lung biopsies that were clinically unhelpful, the reason for failure in approximately one-third of patients was the failure of the procedure to obtain an adequate quantity of lung parenchyma for a meaningful histological analysis.
Biopsies of the lung have been obtained via bronchoscopy for >40 yrs 1–3. Several studies have reported the diagnostic yield and complications of bronchoscopic lung biopsy (BLB) in various patient populations 4, 5. The purpose of the present study was to determine whether information obtained from BLB is useful to clinicians, and how this information is used in the management of patients with diffuse pulmonary disorders.
Many of the published reports have focused on the role of BLB in the diagnosis of diffuse pulmonary diseases and the accuracy of histological diagnosis. The present study, in contrast to earlier studies, was designed to evaluate how BLB results are used by clinicians. The main aim of the study was to assess whether the results of the BLB were clinically useful in the management of patients with diffuse pulmonary disorders.
|
METHODS |
|---|
|
TOPABSTRACTMETHODSRESULTSDISCUSSIONREFERENCES |
|---|
|
RESULTS |
|---|
|
TOPABSTRACTMETHODSRESULTSDISCUSSIONREFERENCES |
|---|
3,300 bronchoscopies were carried out at the Mayo Medical Center. The median (range) patient age was 60 (10–93) yrs, and there were 355 females (54.5%). Indications for BLB are shown in table 1
. A total of 54 BLBs were performed in 16 lung transplant recipients for the indications of pulmonary infiltrate or transplant surveillance. Histopathological diagnoses are shown in table 2. Biopsy results were considered helpful in 494 (75.9%) out of the 651 procedures. Of these, 249 (38.2% of all BLBs) provided clinically useful histopathological diagnoses and the remainder were helpful in excluding certain disorders. In total, 157 (24.1%) of the biopsies were considered not helpful. In 52 (8% of all BLBs), no lung parenchyma was obtained.
|
|
When the BLB result was considered unhelpful, open lung biopsy was performed in 44 (28.6%) out of 154 patients. A specific diagnosis was established by a bronchoscopic procedure performed at the time of BLB (cytology, transbronchial needle aspiration, endobronchial biopsy, cultures of bronchoalveolar lavage fluid or bronchial washings) in 23 out of the 157 BLB procedures with unhelpful results (14.6%).
Malignancy was ultimately diagnosed in 94 (15.6%) out of the 603 patients who underwent BLB. In 66 out of 94 (70.2%), the diagnosis was provided by BLB. Primary lung cancer was diagnosed in 66 (10.9%) out of 603 patients, and metastatic malignancy in 28 (4.6%) out of 603. The diagnostic rate of BLB was 72.7% for primary lung cancer and 64.3% for metastatic malignancy.
Of all BLB procedures, pneumothorax occurred in eight (1.2%) out of 651. Other complications including bleeding and death were not specifically identified as part of this study.
|
DISCUSSION |
|---|
|
TOPABSTRACTMETHODSRESULTSDISCUSSIONREFERENCES |
|---|
The initial experience reported positive biopsy results in 60% of patients who had BLB via flexible bronchoscopy for diffuse bilateral shadows or multiple opacities 5. Subsequent experience described in several studies reported positive results in 82% of cases 9, 10, 14. The substantial clinical usefulness and safety of BLB in diffuse pulmonary disorders has been demonstrated in many studies 15, 16. As a result, BLB is a well-established diagnostic technique used by almost all bronchoscopists, and the flexible bronchoscope is used almost exclusively. In a survey of 1,800 North American bronchoscopists, nearly 70% reported that they performed BLB routinely in diffuse lung disease in nonimmunocompromised patients 17.
By definition, BLB denotes biopsy of lung or pathological processes occurring within the pulmonary parenchyma. Biopsy of peripheral nodules originating in the bronchial wall does not represent BLB. Nevertheless, the term BLB is loosely used in clinical practice as well as literature to describe biopsy of any bronchoscopically invisible lesion. As a result, the interpretation of diagnostic yield from "BLB" of diffuse and localised lesions becomes difficult 18. In the current authors’ analysis, results of biopsies of solitary nodules were excluded and patients who had radiological features of patchy or widespread diffuse parenchymal disease were included. Most, if not all, patients in the present study underwent chest computed tomography evaluation prior to bronchoscopy to guide BLB. However, a standardised algorithm was not used for work-up prior to bronchoscopy.
There is variability in defining the term "diffuse lung disease". In some cases, this term is used to describe bilateral, multilobar parenchymal changes; however, the present authors’ analysis included any ill-defined radiographic lesion, reasoning that a pathological process can be diffuse in a localised area of pulmonary parenchyma. As mentioned previously, BLBs of these types of lesions are performed with the intent to obtain parenchymal lung tissue.
Diffuse interstitial lung disease caused by either benign or malignant processes is a common indication for BLB 19–22. The most common indication for BLB in the current authors’ study was pulmonary infiltrate (patchy or widespread) in 81.9% of cases, followed by multiple pulmonary nodules or nodular infiltrate in 9.1%. Patients with interstitial lung disease were frequently included in the pulmonary infiltrate group, as this was the main indication for BLB listed on the procedure report. Similarly, lung transplant recipients whose indication for BLB was "pulmonary infiltrate" were also included in the group, and those without specific radiographic abnormalities were included in the "lung transplant recipient surveillance" group.
When BLB was introduced into clinical practice, a positive biopsy using the BLB technique was defined as diagnostic histology, histology that supported a diagnosis, or histology consistent with the final diagnosis 4. Indeed, most of the published studies have focused on the diagnostic accuracy of histological analysis of BLB in patients with diffuse lung disorders. In contrast to the earlier reports on BLB, the present study focused on how BLB results are used by clinicians. The main aim of the current study was to assess whether the results of the BLB were clinically useful in the management of patients with diffuse pulmonary disorders. The results of the present study indicate that BLB is a clinically useful test in 75% of procedures. The current analysis showed that of the 25% of BLBs that were clinically unhelpful, the main reason for failure in approximately one-third of these patients was the absence of pulmonary parenchyma, or an inadequate quantity of lung parenchyma, in the biopsy specimen for a meaningful histological analysis. While it is difficult to enumerate every factor underlying this failure, various factors may have contributed to the failure in obtaining adequate lung parenchyma. Some of the common reasons mentioned by the bronchoscopists included excessive patient cough, bleeding, and inadequate placement of biopsy forceps.
Inability to obtain optimal or adequate pulmonary parenchymal specimens is a common problem even when fluoroscopic guidance is used. Proper equipment, technique and use of fluoroscopy will enhance the chance of collecting good biopsy specimens 15. Previous studies also noted the problem of inadequate lung tissue from BLB in up to 20% of patients 1, 3.
Bronchoscopic biopsy of very localised lesions yields a diagnostic rate of 60% in primary lung cancer and of 50% in metastatic cancer, when these tumours present as peripheral lung nodules 18. Biopsy of lesions >2.0 cm in diameter provides a diagnostic yield in >60% of cases, whereas lesions <2.0 cm in diameter yield a diagnosis in <25% of cases 18. Diagnostic rates are likely to be lower if nodular or localised lesions are caused by nonmalignant processes. In the present cohort of patients with patchy or widespread diffuse parenchymal disease, malignancy was ultimately diagnosed in 15.6%. The diagnostic rate of BLB was 72.7% in primary lung cancer and 64.3% in metastatic cancer.
It is not uncommon for BLB pathology results to return without diagnostic abnormality. It can be difficult to know whether this is due to sampling error, or whether there truly is an absence of significant pathology. In the current study, an adequate lung parenchymal biopsy without a specific diagnostic abnormality was considered clinically helpful in 55% of the patients.
The current study is limited by its retrospective nature, and the difficulty in determining how results from BLB were used. The present authors attempted to follow strict criteria for definitions of usefulness or unusefulness; however, in some cases a degree of subjectivity was required. The bronchoscopy reports did not uniformly report the number of biopsies taken, so the current authors were unable to comment on the relationship between number of biopsies and diagnostic yield or clinical utility.
Since the 1990s, high-resolution computed tomography and video-assisted thoracoscopic lung biopsy have been emerging techniques in establishing the diagnosis of diffuse lung disorders. Bronchoalveolar lavage has also emerged as an important diagnostic tool that has obviated the need for bronchoscopic lung biopsy in many clinical conditions. Further improvements in these and other techniques may lead to a decline in the need for bronchoscopic lung biopsy. In the USA alone, >500,000 bronchoscopies are performed each year 23, and 15% of these procedures include bronchoscopic lung biopsy 24, 25. It is clear that bronchoscopic lung biopsy remains an important diagnostic method for the evaluation of patients with diffuse lung diseases 15, 16.
|
REFERENCES |
|---|
|
TOPABSTRACTMETHODSRESULTSDISCUSSIONREFERENCES |
|---|
This article has been cited by other articles:
|
|
 |
|
  R. MacJannette, J. Fiddes, K. Kerr, and O. Dempsey Is bronchoscopic lung biopsy helpful in the management of patients with diffuse lung disease? Eur. Respir. J., May 1, 2007; 29(5): 1064 - 1064. [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
