Abstract
Background:
Central airway obstruction (CAO) is a serious condition that affects patients with both benign and malignant diseases. Timely recognition of CAO is crucial for prompt intervention aimed at improving the symptoms and quality of life of these patients. The aim of this study is to evaluate the formal radiology reporting of CAO and its impact on patients’ outcomes.
Methods:
The medical records of patients who underwent advanced therapeutic bronchoscopy for CAO from August 2013 to September 2014 were retrospectively reviewed. Three researchers each reviewed 14 of the 42 formal radiology reports that were performed at 16 different medical and radiology centers.
Patient characteristics were reported as means, medians, and standard deviations for continuous variables, and as frequencies and relative frequencies for categorical variables.
Results:
Out of 42 patients who underwent advanced bronchoscopy for planned therapeutic intervention, only 30 had radiology and pulmonology concordance about the airway findings of CAO. This is an agreement rate of 71.4% [95% confidence interval (CI): 56.7–83.3%] or a disagreement rate of 28.6% (95% CI: 16.7–43.3%). The radiology reports did not mention 31% of CAO on CT scans. The median time from CT imaging to bronchoscopy was significantly longer in patients with CAO not reported by the radiologists (21 versus 10 days; p = 0.011). Most patients improved postoperatively with no significant difference between the two groups.
Conclusions:
Findings of CAOs were not described in a significant proportion of radiology reports. This results in significant delay in bronchoscopic airway management.
Keywords: airway obstruction, interventional pulmonology, radiology report
Introduction
At the time of clinical presentation, the majority of patients with malignant central airway obstruction (CAO) are at an advanced stage and, therefore, require palliation therapy to relieve symptoms and improve the quality of life [Simoff et al. 2013; Simoff, 2001; Jeon et al. 2006; Lo et al. 2000]. Primary tracheal or bronchial cancers may also present with symptoms of CAO at their earlier stages. In such cases, the ideal treatment would be bronchoscopic intervention for airway management followed by surgical resection in patients who can tolerate the surgery [Huang et al. 2003; Meyers and Mathisen, 1997]. Benign conditions such as the post-intubation tracheal stenosis, post-transplant airway complications, tracheomalacia, and benign tumors can affect the central airways and cause focal or diffuse stenosis or obstruction [Ahn et al. 2011].
In most cases, advanced bronchoscopic procedures are performed as outpatient procedures, and many patients demonstrate immediate postoperative symptomatic relief [Ernst et al. 2004]. Most patients who have malignant CAO present with worsening or new respiratory symptoms. These symptoms are nonspecific and could therefore be explained by malignant disease progression or other pulmonary manifestations rather than airway obstruction. It is only after detecting CAO by chest imaging that a patient is referred for intervention.
CT scan is helpful in different diseases that affect the tracheobronchial tree including intraluminal and extrinsically compressing tumors [Ahn et al. 2011; Jabbardarjani et al. 2009; Kwong et al. 1992]. Expedited intervention is essential for a satisfactory outcome with improvement of respiratory scores, quality of life, and possible survival benefit in patients with malignant airway disease [Razi et al. 2010]. Timely intervention for airway management requires a high degree of vigilance. In most cases, this depends on the radiologists reporting CAO on the chest imaging study to alert the ordering physician, which may results in prompt referral. Currently, there are no studies comparing the presence and degree of CAO as perceived by the radiologists and the intervention pulmonologists reviewing the same chest CT scan. The aim of this study is to evaluate the formal radiology reporting of CAO and its impact on patients’ outcomes. The clinical implication is important as early identification of airway obstruction can lead to timely referral, early intervention, improved outcome and quality of life.
Materials and methods
The study protocol (BDR_051814) was approved by the Institution Review Board. Informed consent was waived due to the retrospective nature of the study. Roswell Park Cancer Institute is a regional tertiary care referral center for patients with lung cancer. All patients who underwent therapeutic bronchoscopy for CAO were included in this study. Airway intervention cases performed subsequent to the initial procedure were excluded as the diagnosis of airway obstruction was already well established. The medical records of patients who underwent advanced therapeutic bronchoscopy for CAO by interventional pulmonary service at our institution from August 2013 to September 2014 were reviewed. Three researchers, each reviewed 14 of the 42 formal radiology reports that were performed at 16 different facilities.
The chest CT scans were performed with or without contrast or were part of positron emission tomography/computed tomography (PET/CT) imaging study. Depending on the patients’ presentations, diagnostic indications and institutional preferences and protocols, the chest CT of various thicknesses had been performed.
During the initial visit to the interventional pulmonology service, the formal radiology report and the chest CT images were reviewed as part of routine initial assessment. The therapeutic bronchoscopic procedure was scheduled based on the interventional pulmonology (IP) interpretation of the actual CT images raising the concern of CAO amenable to bronchoscopic intervention. Although the tumor may have possibly grown between the CT imaging and the bronchoscopy procedure, this should have no influence on the discrepancy between the radiology reports and IP interpretation of the same CT imaging.
Initial central airway assessment of the interventional pulmonary team and the final findings on bronchoscopy evaluation were noted from the electronic medical record. The modalities of therapeutic bronchoscopy such as rigid bronchoscopy, ablation, stent, etc., were noted. Relationship of the timing of the radiology report with the therapeutic bronchoscopy was explored along with patient outcomes. CAO severity was based on the bronchoscopy report. In the radiology reports, there was no mention of any specific techniques to measure airway obstructions. During bronchoscopy, the severity of CAO was estimated using the scope size that can bypass the obstruction in combination with controlled radial expansion (CRE) balloon.
A total of 47 advanced bronchoscopy therapeutic interventions were performed. A total of 41 patients were initially planned for advanced therapeutic intervention including rigid bronchoscopy, and one patient was scheduled as diagnostic endobronchial ultrasound (EBUS) and converted to a therapeutic procedure after discovering intraoperative malignant CAO. Five of the 47 cases had repeated bronchoscopic procedures and, since the diagnosis of CAO was already established, were excluded from the study analysis. We included symptomatic patients with CAO of more than 50% due to benign or malignant diseases. Symptoms included shortness of breath, hemoptysis, postobstructive pneumonia, lung collapse, and respiratory failure. All patients had chest CT scans performed before their initial evaluation by the interventional pulmonology. All patients underwent bronchoscopy under general anesthesia with endotracheal intubation, laryngeal mask airway, or rigid bronchoscopy using conventional ventilation. Manual jet ventilation was available if needed. The flexible therapeutic, regular and ultrathin bronchoscopes (Olympus America Inc., Center Valley, PA) were used in most cases. The rigid bronchoscope and tracheoscope (Bryan Corporation, Woburn, MA), argon plasma coagulation (APC; ERBE, USA, Inc.), electrocautery (ERBE, USA, Inc.), or laser (Biolitec, Germany, Inc.) were used in the majority of cases. In many patients, covered metallic or silicone stents were deployed to maintain airway patency. Patients were referred to palliative radiation therapy or hospice when indicated.
Statistical analysis
Patient characteristics were reported as means, medians, and standard deviations for continuous variables; and as frequencies and relative frequencies for categorical variables. Comparisons were made using the Mann–Whitney U and Fisher’s exact tests for continuous and categorical variables, respectively. The rate of agreement between radiology and pulmonology was reported as 95% confidence intervals (CIs), obtained using Jeffrey’s prior method. The association between overall survival (time from imaging and time from bronchoscopy) and both diagnosis and agreement (between radiology and pulmonology) were summarized using standard Kaplan–Meier methods, with comparisons made using the log-rank test. All analyses were completed in SAS v9.4 (Cary, NC) at a significance level of 0.05; therefore, a p value less than 0.05 denotes a statistically significant result.
Results
During a 12-month period, 42 patients underwent therapeutic bronchoscopy and were included in the analysis. As a regional and local referral cancer center, we evaluated patients coming from several different places. Because of this, the radiology interpretations originated from 16 different institutions and radiology centers including our institution. Out of 42 chest CT scans reviewed in this study, four of the chest CT scans were part of PET/CT scans, 29 were chest CT scans of 5 mm thickness cuts, and nine were chest CT scans with thickness cuts of less than 5 mm. A total of 31 of the 42 chest CT scans were performed with intravenous contrast. Three-dimensional reconstruction was not performed in any of the patients. The diagnosis of CAO was established during bronchoscopy with an average obstruction severity of 87.9 % (range 50–100%).
A total of 35 patients (83.3%) underwent rigid bronchoscopy, and 34 patients (81%) underwent combined bronchoscopic modalities. A total of 20 patients received stent placement, seven were metallic and 13 were silicone of which eight were tracheal or secondary carina Y-stents. In five patients, no therapeutic modalities were used because in addition to CAO, there was tumor involving the distal airways and therefore only diagnostic procedures were performed.
Out of 42 patients diagnosed by bronchoscopy with CAO, 30 had concordance between radiology and IP reporting on the finding of presence of CAO. This represented an agreement rate of 71.4% (95% CI: 56.7–83.3%) or a disagreement rate of 28.6% (95% CI: 16.7–43.3%). The radiology reports did not mention 31% of CAO on CT scans, and in only one of these patients (7.7%), CAO was not reported during initial interventional pulmonology assessment. We divided the patients in two groups. Group 1 includes patients who had CAO that was not described in the radiology reports. Group 2 includes the patients who had CAO that was described in the radiology reports.
Table 1 presents the patient characteristics by radiographic assessment. Univariate analysis showed that there was a significant association between radiographic airway obstruction detection and age, time from referral to bronchoscopy, and time from CT imaging to bronchoscopy. Patients with CAO in group 2 were younger than patients in group 1 (median age: 59 versus 63, p = 0.048). The median time from CT imaging to bronchoscopy was significantly longer in patients with CAO in group 1 compared with those in group 2 (21 versus 10 days; p = 0.011). The median time from referral to bronchoscopy was also significantly longer in patients of group 1 compared with patients in group 2 (8 versus 3 days; p = 0.045; see Table 2). This demonstrates that recognition of airway obstruction based on radiology report results in earlier airway intervention. There was no statistical difference in types of modalities used between the two groups. Although our sample size and event rate are small, there appeared to be no significant difference in survival between the two groups (median of 5.7 and 5.4 months for group 1 and group 2, respectively, p = 0.078).
Table 1.
Characteristics of patients with airway obstruction based on radiography reporting.
| No CAO reported (Group 1) | CAO reported (Group 2) | Overall | p value | ||
|---|---|---|---|---|---|
| Overall | N | 13 (31.0) | 29 (69.0) | 42 (100%) | |
| IP assessment | None Detected | 1 (7.7%) | 1 (2.4%) | 0.310 | |
| Narrowing Detected | 12 (92.3%) | 29 (100.0%) | 41 (97.6%) | ||
| Severity of Obstruction (%) | Mean/SD/N | 81.88/16.46/8 | 90.24/12.19/21 | 87.93/13.73/29 | 0.131 |
| Median/Min/Max | 82.50/50.00/100.00 | 95.00/60.00/100.00 | 90.00/50.00/100.00 | ||
| Age (years) | Mean/SD/N | 65.08/9.72/13 | 58.10/9.98/29 | 60.26/10.31/42 | 0.048 |
| Median/Min/Max | 63.00/52.00/83.00 | 59.00/27.00/75.00 | 60.00/27.00/83.00 | ||
| Gender | Male | 5 (38.5%) | 13 (44.8%) | 18 (42.9%) | 0.748 |
| Female | 8 (61.5%) | 16 (55.2%) | 24 (57.1%) | ||
| Race | White | 13 (100.0%) | 22 (75.9%) | 35 (83.3%) | 0.209 |
| African American | 6 (20.7%) | 6 (14.3%) | |||
| Other | 1 (3.4%) | 1 (2.4%) | |||
| Diagnosis | Adeno Lung Ca | 7 (53.8%) | 9 (31.0%) | 16 (38.1%) | 0.741 |
| Squamous Lung Ca | 2 (15.4%) | 9 (31.0%) | 11 (26.2%) | ||
| Other Lung Ca | 1 (7.7%) | 3 (10.3%) | 4 (9.5%) | ||
| Other Ca | 2 (15.4%) | 5 (17.2%) | 7 (16.7%) | ||
| Benign | 1 (7.7%) | 3 (10.3%) | 4 (9.5%) | ||
| Dyspnea | None | 6 (22.2%) | 6 (15.0%) | 0.230 | |
| With Exertion | 3 (23.1%) | 4 (14.8%) | 7 (17.5%) | ||
| At Rest | 10 (76.9%) | 17 (63.0%) | 27 (67.5%) | ||
| Tumor Debulking | No | 4 (30.8%) | 16 (55.2%) | 20 (47.6%) | 0.190 |
| Yes | 9 (69.2%) | 13 (44.8%) | 22 (52.4%) | ||
| Tumor Ablation | No | 4 (30.8%) | 13 (44.8%) | 17 (40.5%) | 0.505 |
| Yes | 9 (69.2%) | 16 (55.2%) | 25 (59.5%) | ||
| Balloon Dilation | No | 3 (23.1%) | 10 (34.5%) | 13 (31.0%) | 0.719 |
| Yes | 10 (76.9%) | 19 (65.5%) | 29 (69.0%) | ||
| Airway Stenting | No | 8 (61.5%) | 14 (48.3%) | 22 (52.4%) | 0.514 |
| Yes | 5 (38.5%) | 15 (51.7%) | 20 (47.6%) | ||
| Laser | No | 12 (92.3%) | 28 (96.6%) | 40 (95.2%) | 0.528 |
| Yes | 1 (7.7%) | 1 (3.4%) | 2 (4.8%) | ||
| APC | No | 7 (53.8%) | 16 (55.2%) | 23 (54.8%) | 1.000 |
| Yes | 6 (46.2%) | 13 (44.8%) | 19 (45.2%) | ||
| Electrocautery | No | 13 (100.0%) | 28 (96.6%) | 41 (97.6%) | 1.000 |
| Yes | 1 (3.4%) | 1 (2.4%) | |||
| Rigid Bronchoscopy | No | 2 (15.4%) | 5 (17.2%) | 7 (16.7%) | 1.000 |
| Yes | 11 (84.6%) | 24 (82.8%) | 35 (83.3%) | ||
| Yes | 7 (70.0%) | 11 (52.4%) | 18 (58.1%) | ||
| Malignant? | Benign | 3 (10.3%) | 3 (7.1%) | 0.540 | |
| Malignant | 13 (100.0%) | 26 (89.7%) | 39 (92.9%) |
APC, argon plasma coagulation; Ca, cancer; CAO, central airway obstruction.
Table 2.
Outcome of patients based on radiology reporting of airway obstruction on chest CT scan.
| None reported (Group 1) | Narrowing reported (Group 2) | Overall | p value | ||
|---|---|---|---|---|---|
| Time: Imaging to Referral (days) | Mean/SD/N | 25.00/33.35/13 | 8.21/8.26/29 | 13.40/20.83/42 | 0.072 |
| Median/Min/Max | 14.00/0.00/118.00 | 4.00/0.00/27.00 | 7.50/0.00/118.00 | ||
| Time: Referral to Bronchoscopy (days) | Mean/SD/N | 8.00/7.26/13 | 5.34/9.78/29 | 6.17/9.07/42 | 0.045 |
| Median/Min/Max | 8.00/1.00/27.00 | 3.00/0.00/53.00 | 4.00/0.00/53.00 | ||
| Time: Imaging to Bronchoscopy (days) | Mean/SD/N | 33.00/35.75/13 | 13.55/14.18/29 | 19.57/24.38/42 | 0.011 |
| Median/Min/Max | 21.00/2.00/134.00 | 10.00/0.00/70.00 | 14.00/0.00/134.00 | ||
| Post-Op Clinical Improvement | No Yes |
3 (30.0%) 7 (70%) |
10 (47.6%) 11 (52.4%) |
13 (41.9%) 18 (58.1%) |
0.452 |
There was no difference in CAO severity between the two groups. There was a significant variation in description of CAO in radiology reports. A total of 14 different terminologies were used to describe CAO in the 29 patients reported by radiologists (group 2); see Table 3. None of these 14 terminologies were used to describe the findings in group 1. For the 13 patients in group 1, the chest CT reports described variable chest abnormalities, such as lung tumor extending to the hilum, enlarged mediastinal or hilar lymphadenopathy, and mediastinal mass. Most patients had improvement in respiratory symptoms in both groups (70% in group 1 and 52.4% in group 2). In spite of this fact, whether the CAO was detected early due to description in radiology report or by clinical/imaging review by Interventional Pulmonologist, there was no statistical difference between the two groups (p = 0.452). A total of 11 of the 42 patients did not have a documented clinical follow up mostly because there were referred to outpatient hospice or different institutions. The discordance was similar whether the imaging was performed and interpreted at our institution or the community referring centers. Out of 42 patients, 21 patients had their CT scan performed at our institution and 21 at outside institutions. Out of 13 patients with CAO not reported by radiologist, six were from our institution and seven were from outside community institutions. The patients were referred by primary care physicians, pulmonologists, medical or thoracic oncologists, and emergency physicians. Out of 42 patients, 29 were referred for airway obstruction and 13 patients were referred for other symptoms such as dyspnea, hemoptysis, and hypoxia. However, the reasons for patients’ referral did not correspond to the chest CT finding of CAO in all cases. Out of the 29 patients who were referred for airway obstruction, five did not have CAO reported on chest CT scan. In addition, out of the 13 patients who were referred for reasons other than airway obstruction, five did have CAO reported on chest CT scans.
Table 3.
Various descriptions of the airway obstruction in radiology reports.
| Description of the CAO | Patients (n = 29) |
|---|---|
| Collapse/atelectasis | 3 |
| Narrowing | 9 |
| Obstruction | 2 |
| Compression | 1 |
| Post-obstruction | 1 |
| Obliteration | 1 |
| Occlusion | 2 |
| Encasement | 1 |
| Endobronchial extension | 1 |
| Filling defect | 2 |
| Closure | 1 |
| Stenosis | 1 |
| Mass | 3 |
| Airway density | 1 |
Complications
There was no procedural-related mortality and no life-threatening complications. Four patients (9.5%) had complications (one intraoperative atrial fibrillation with rapid ventricular response, one postoperative wheezing and stridor, one postoperative dyspnea, and one left upper lip swelling).
Discussion
We have reported the first study that looks at the formal radiological reporting of cases of CAO that required advanced airway interventions. Our findings show that the presence of CAO is not described in radiology reports of almost one third of these patents. This results in significant delay in performing therapeutic bronchoscopic intervention when possible. Even when CAO was reported, there was significant variation in the descriptive terminology used by radiologists and radiology centers.
Dedicated interventional bronchoscopy programs may yield a significant increase in CAO patients’ referrals from outside institutions. These patients underwent multimodality therapy including tumor ablation with laser, APC, and electrocautery, balloon dilation, and airway stenting [Noppen et al. 1997; Brichet et al. 1999; Mughal et al. 2005; Freitag et al. 1997; Ost et al. 2014; Okiror et al. 2015]. Although large, randomized, controlled trials are lacking, retrospective and prospective data show notable improvement in patients’ outcome and quality of life with CAO bronchoscopic management [Jeon et al. 2006; Ernst et al. 2004].
Early diagnosis of CAO based on clinical and imaging findings is essential for prompt bronchoscopic intervention or rarely for surgical operation. Patients with untreated CAO have bad prognosis with survival ranging from 1 to 2 months [Macha et al. 1994; Walser et al. 2004]. The quality of life of these patients is also poor, with many patients dying of asphyxia in palliative care facilities or on mechanical ventilatory support. Therefore, it remains important to treat patients with CAO in a timely fashion. Direct inspection of airways with bronchoscopy is the gold standard for diagnosing central airway obstruction. Newer modalities of CT scan (i.e. multi-planar and three-dimensional reconstructions, virtual bronchoscopy) have shown improved detection rate of airway obstruction and planning the therapeutic approach [LoCicero et al. 1996; Sundarakumar et al. 2011; Finkelstein et al. 2004; Righini et al. 2010; Ferretti et al. 2007; Colt et al. 2013].
This study highlights the importance of precise reporting of CAO as it could expedite airway interventions. The terminology used in reporting CAO by CT scan were widely variable and could lead to a delay in referring these patients for intervention. Several studies have shown quality of life and symptomatic improvement with trends to survival benefit when patients with CAO were bronchoscopically managed. Interestingly, in cases when airway obstruction were not reported by the radiologist, this led to significant delay to therapeutic bronchoscopy (median: 10 versus 21 days). This large latency period probably resulted in prolonged symptomatic period since the majority of these patients improved after bronchoscopic intervention. The lives of patients with malignant CAO may be shortened or incapacitated by the magnitude and gravity of their disease, and delaying palliation has significant adverse effect on their quality of life and may increase cost of care.
There are several limitations to this study. Although CT imaging was performed at 16 centers in western New York, this area may not represent the radiology practices in other places around the country. The study is limited by its retrospective nature and by potential and inherent referral bias based upon tumor type and stage and patient comorbidities. Although our institution is a premier regional referral center for lung cancer management and airway intervention, it is possible that some patients were referred to other tertiary care facilities offering airway intervention or radiation oncologists. Because of the retrospective nature of our study, we do not have specific information about the training of the radiologists or the volume of patients of the most of the radiology centers involved in this study. Another possible limitation of our study is that the severity of CAO is estimated during bronchoscopy under general anesthesia, which can be different when compared with chest CT that is generally performed at end inspiration. However, all except one of the therapeutic bronchoscopic interventions were scheduled based on CT review of the IP team, which suggests that CT evaluation by the clinical team did offer clues to the possibility of CAO. Trained interventional pulmonologists performed all cases at our center and this may not be representative of other bronchoscopy practices where different interventional pulmonologists, thoracic surgeons, and general pulmonologists perform the advanced bronchoscopy. This study did not directly compare the performance of radiologist with interventional pulmonologist but looked at the pattern of initial recognition of CAO based on radiology reports in one geographic area in a small group of patients. The interventional pulmonary team had the advantage of being able to personally evaluate the patient along with the ability to review the chest CT. Additional important parameters such as impact on quality of life of patients and financial analysis of impact of delay in recognition of CAO could not be done. Similar delay in radiation treatment for airway obstruction is possible but was not explored in this study. A prospective multicenter study involving advanced bronchoscopy practices with diverse training and expertise and wider geographic area could provide additional compelling data.
Conclusions
A significant number of patients with CAO had their finding not described at all on radiology reports based on chest CT scans. This can lead to significant delay from imaging to advanced bronchoscopic interventions. The results of this study raise awareness about the importance of prompt recognition and precise reporting of CAO using standardized nomenclature to allow timely airway interventions.
Footnotes
Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article.
Conflict of interest statement: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Contributor Information
Kassem Harris, Roswell Park Cancer Institute, Department of Medicine, Interventional Pulmonary Section University at Buffalo, State University of New York, Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Elm and Carlton streets, Buffalo, NY 14623, USA.
Abdul Hamid Alraiyes, Roswell Park Cancer Institute, Department of Medicine, Interventional Pulmonary Section University at Buffalo, State University of New York, Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, New York, USA.
Kristopher Attwood, Roswell Park Cancer Institute, Department of Biostatistics and Bioinformatics.
Kush Modi, University at Buffalo, State University of New York, Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, New York, USA.
Samjot S. Dhillon, Roswell Park Cancer Institute, Department of Medicine, Interventional Pulmonary Section University at Buffalo, State University of New York, Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, New York, USA
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