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DOI:10.2214/AJR.04.1893
AJR 2006; 186:1304-1313
© American Roentgen Ray Society


Pictorial Essay

Benign Tumors of the Tracheobronchial Tree: CT-Pathologic Correlation

Jeong Min Ko1, Jung Im Jung1, Seog Hee Park1, Kyo Young Lee2, Myung Hee Chung1, Myeong Im Ahn1, Ki Jun Kim1, Yo Won Choi3 and Seong Tai Hahn1

1 Department of Radiology, College of Medicine, The Catholic University of Korea, 62 Yeouido-dong, Youngdungpo-gu, Seoul 150-713, Korea.
2 Department of Pathology, Kangnam St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
3 Department of Radiology, Hanyang University Hospital, Seoul, Korea.

Received December 13, 2004; accepted after revision March 3, 2005.

 
Address correspondence to J. I. Jung (jijung{at}catholic.ac.kr).


Abstract
Top
Abstract
Introduction
Hamartoma
Leiomyoma
Lipoma
Neurogenic Tumor
Inflammatory Polyp...
Amyloidoma
Papilloma
Pleomorphic Adenoma (Benign...
Other Benign Tumors
References
 
OBJECTIVE. The purpose of this essay is to illustrate the CT findings of variable benign tumors of the tracheobronchial tree and to correlate the CT and pathologic findings in 17 patients.

CONCLUSION. The tracheal tumors were eccentric, well-defined, polypoid masses in all cases. The endobronchial tumors were masses confined within the bronchus in all cases, and atelectasis or pneumonia of the distal parenchyma was frequently associated. Of the six hamartomas, one was a fatty mass, and two were nodules with calcification. The others were soft-tissue-density nodules. The lipomas manifested as fat density on CT scans in both cases. The other benign tumors were low-attenuating, soft-tissue-density masses without characteristic findings on CT scans.

Keywords: airway • chest • CT • lung


Introduction
Top
Abstract
Introduction
Hamartoma
Leiomyoma
Lipoma
Neurogenic Tumor
Inflammatory Polyp...
Amyloidoma
Papilloma
Pleomorphic Adenoma (Benign...
Other Benign Tumors
References
 
Most tumors of the tracheobronchial tree are malignant. Benign tumors are quite rare (ca. 1.9% of all lung tumors). Unlike malignant tumors, many benign neoplasms are slow growing and present with symptoms related to bronchial obstruction [1]. Benign lesions of the trachea often go unrecognized for months or even years. As a result, patients with such tumors often undergo prolonged treatment for obstructive lung disease or asthma.

It is often difficult to identify benign tracheal lesions on routine chest radiographs. The clinical and radiographic features of these tumors are often indistinguishable from those of malignant tumors. Many of these lesions have similar radiographic features. These radiographic findings are often nonspecific and include atelectasis, pneumonia, bronchiectasis, and mediastinal shifts [1]. Early recognition and diagnosis of these benign lesions may allow conservative treatment and excellent patient outcome.

The CT findings of benign tumors of the tracheobronchial tree are rarely reported. Only a few case reports of the CT findings of benign tumors of the tracheobronchial tree have appeared in the literature [2, 3]. In those cases, CT revealed the tumor and showed its size and extent, findings helpful for surgical planning. More important, CT findings excluded contiguous mediastinal and parenchymal lung involvement [3]. In most of the reported cases CT showed masses confined within the tracheobronchial lumen without evidence of adjacent invasion. CT findings also aid in definitive diagnosis of fatty tumor within the tracheobronchial lumen because CT is highly specific and sensitive in the detection of fat [2].

We retrospectively reviewed the CT scans of 17 patients with pathologically proven benign tracheobronchial tumors. The nine male and eight female patients were 16-76 years old. The chief complaints were chronic cough and sputum (n = 10), progressive dyspnea or asthma attack (n = 3), hemoptysis (n = 3), and fever (n = 1). One patient had no specific complaint. The tumors were classified according to the anatomic location of the lesions in the trachea (n = 5), bronchus intermedius (n = 3), lobar bronchus (n = 6), and segmental bronchus (n = 3). Pathologic diagnoses were hamartoma (n = 6), leiomyoma (n = 3), lipoma (n = 2), schwannoma (n = 2), inflammatory polyp (n = 1), amyloidoma (n = 1), papilloma (n = 1), and pleomorphic adenoma (n = 1). We present the CT findings of benign tracheobronchial tumors correlated with the histopathologic findings.


Hamartoma
Top
Abstract
Introduction
Hamartoma
Leiomyoma
Lipoma
Neurogenic Tumor
Inflammatory Polyp...
Amyloidoma
Papilloma
Pleomorphic Adenoma (Benign...
Other Benign Tumors
References
 
Hamartoma is defined as a mass resulting from the abnormal growth and mixture of tissue elements or an abnormal proportion of a single element of tissue normally present in an organ [1]. Hamartoma in the lung is the most common benign tumor. Arrigoni et al. [4] reviewed 130 benign tumors, of which 77% were hamartomas. Only 3% of the hamartomas were endobronchial. In a large series of benign endobronchial tumors, hamartoma was the most common type (70%) [1]. Endobronchial hamartoma is a special form of the usual intrapulmonary hamartoma. It originates from a large bronchus, grows into the lumen, and obstructs the bronchi before becoming large [2].


Figure 1
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Fig. 1A —75-year-old man with endobronchial hamartoma with fat attenuation in bronchus intermedius. Patient had had recurrent pneumonia for several years. CT scan at level of right bronchus intermedius obtained after administration of contrast material shows horseshoe-shaped, fat-attenuated endobronchial lesion in right bronchus intermedius.

 


Figure 2
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Fig. 1B —75-year-old man with endobronchial hamartoma with fat attenuation in bronchus intermedius. Patient had had recurrent pneumonia for several years. Photomicrograph of specimen shows bland cartilage, columnar epithelium, and interposed fat (arrows) consistent with hamartoma. (H and E, x100)

 


Figure 3
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Fig. 2 —Endobronchial hamartoma as mass containing calcifications in bronchus intermedius of patient with situs inversus totalis. Contrast-enhanced CT scan shows calcified endobronchial mass (arrow) with fibrous cap in bronchus intermedius.

 
Intrapulmonary and endobronchial hamartomas contain cartilage, fat, fibrous tissue, and an epithelial component. It is reported, however, that endobronchial lesions tend to have relatively more fat than do parenchymal lesions. This finding may be attributable to the relative abundance of fat in the bronchial walls as opposed to the lung parenchyma. Unlike the more common parenchymal hamartoma, which tends to present as an asymptomatic solitary lesion, endobronchial hamartoma is often symptomatic because of airway obstruction, which can cause cough, hemoptysis, dyspnea, and obstructive pneumonia [1].

Chest radiography often shows the sequelae of endobronchial obstruction. These include atelectasis, postobstructive pneumonia, and bronchiectasis. Endobronchial mass lesions may be poorly depicted or not depicted at all on chest radiographs [1].

CT scans reflect the various tissue components of hamartoma. Ahn et al. [2] reported the CT findings of endobronchial hamartoma in three patients. One lesion was a mass of fat attenuation, and the pathologic examination showed the lesion was composed mainly of fatty tissue (Figs. 1A and 1B). Another lesion exhibited soft-tissue attenuation and contained a higher-attenuation core composed of connective tissue stroma, islands of cartilage, and occasional areas of calcification and ossification (Fig. 2). In the third patient, the mass attenuation was similar to that of muscle. The lesion was composed of connective tissue stroma containing fat, lymphoid tissue, and smooth muscle in various proportions (Figs. 3A, 3B, and 3C). Ahn et al. [2] concluded that the CT finding of endobronchial hamartoma is an endobronchial mass with obstructive pneumonia. However, in the case of some masses containing fat or calcification, a specific diagnosis of hamartoma can be made.


Figure 4
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Fig. 3A —62-year-old man with endobronchial hamartoma that manifested as soft-tissue-attenuating mass. The patient had complained of cough for 6 months. Contrast-enhanced CT scan shows low-attenuation (47 H) endobronchial mass (white arrow) obstructing right upper lobe bronchus.

 

Figure 5
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Fig. 3B —62-year-old man with endobronchial hamartoma that manifested as soft-tissue-attenuating mass. The patient had complained of cough for 6 months. Three-dimensional shaded-surface display reconstruction image shows bronchial obstruction.

 

Figure 6
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Fig. 3C —62-year-old man with endobronchial hamartoma that manifested as soft-tissue-attenuating mass. The patient had complained of cough for 6 months. Excised mass is round and lobulated with firm consistency. Pathologic diagnosis was hamartoma.

 

Leiomyoma
Top
Abstract
Introduction
Hamartoma
Leiomyoma
Lipoma
Neurogenic Tumor
Inflammatory Polyp...
Amyloidoma
Papilloma
Pleomorphic Adenoma (Benign...
Other Benign Tumors
References
 
Primary pulmonary leiomyoma is extremely uncommon, constituting approximately 2% of benign lung tumors. Approximately 45% of pulmonary leiomyomas are endobronchial; the other lesions occur in the lung parenchyma and trachea [1].


Figure 7
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Fig. 4 —39-year-old woman with tracheal leiomyoma. Contrast-enhanced CT scan shows smooth, round, 43-64 H intraluminal mass with wide attachment to right posterolateral wall of trachea.

 
The histologic findings of leiomyoma are composed of long interlacing fascicles of spindle cells with abundant elongated eosinophilic cytoplasm. Hypocellularity is often associated with stromal hyalinization and a marked decrease of the vascular framework. The nuclei are oval and indented with delicate chromatin and small inconspicuous nucleoli and are devoid of atypical mitoses. Leiomyoma can be difficult to differentiate from fibroma, neurofibroma, and schwannoma at light microscopy alone. However, immunoperoxidase staining for vimentin, actin, and S-100 protein has positive results in leiomyoma [1].

Tracheal leiomyoma arises from the smooth muscle in the tracheal wall, typically along the membranous portion of the lower third of the trachea because of the abundant smooth-muscle fibers in this area [3]. Most patients with tracheal leiomyoma are 15-72 years old, and there is no sex predominance. Even though it is benign, tracheal leiomyoma can be lethal because of tracheal obstruction [3].


Figure 8
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Fig. 5A —57-year-old woman with endobronchial leiomyoma. Contrast-enhanced CT scan shows low-attenuation (42 H) endobronchial mass (arrow) obstructing apical segmental bronchus of right upper lobe.

 


Figure 9
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Fig. 5B —57-year-old woman with endobronchial leiomyoma. Lung specimen shows mass (arrows) in segmental bronchus.

 


Figure 10
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Fig. 5C —57-year-old woman with endobronchial leiomyoma. Photomicrograph shows spindle-shaped cells with oval nuclei arranged in parallel bundles and whorls typical of leiomyoma. (H and E, x400)

 


Figure 11
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Fig. 5D —57-year-old woman with endobronchial leiomyoma. Desmin immunoreactivity (red) is evident in tumor cells.

 
CT findings of tracheal leiomyoma are a smooth, intraluminal soft-tissue mass limited to the tracheal wall with occasional areas of cystic degeneration due to poor vascularization (Fig. 4) [3]. Like those of other benign tracheal masses, the CT characteristics of leiomyoma are not specific, but CT is helpful in determining the extent of tracheal involvement and involvement of adjacent structures [3]. Diagnosis requires biopsy, which must be performed with caution because death due to tracheal obstruction or bleeding during endoscopic resection has been reported. Thoracotomy with wide tracheal resection may be needed for complete excision of the typically broad base of this neoplasm. Incomplete excision often results in recurrence [3]. CT findings of endobronchial leiomyoma have not yet been reported in the literature. Our patient had a soft-tissue-density nodule that was confined to the segmental bronchus and occluded the lumen (Figs. 5A, 5B, 5C, and 5D).


Figure 12
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Fig. 6A —47-year-old man with lipoma who had fever and chills for several days. Contrast-enhanced chest CT scan shows -88 H rounded fatty mass (arrow) obstructing right middle lobe bronchus.

 


Figure 13
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Fig. 6B —47-year-old man with lipoma who had fever and chills for several days. Bronchoscopic photograph shows polypoid, whitish endobronchial mass.

 


Figure 14
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Fig. 6C —47-year-old man with lipoma who had fever and chills for several days. Histologic photograph shows mature adipocytes consistent with lipoma. (H and E, x400)

 


Figure 15
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Fig. 7A —37-year-old man with tracheal lipoma. CT scan shows 1.5-cm, -100 H, well-defined, pedunculated, intraluminal fatty mass in trachea.

 


Figure 16
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Fig. 7B —37-year-old man with tracheal lipoma. Pathologic specimen contains polypoid mass with glistening capsule and homogeneously yellow cut surfaces.

 


Figure 17
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Fig. 8A —34-year-old-woman with endobronchial schwannoma in bronchus intermedius. The patient had chronic cough, and sputum was present. Contrast-enhanced CT scan shows low-attenuation (45 H) endobronchial mass (arrow) obstructing bronchus intermedius. Atelectasis of right middle and lower lobes is evident.

 


Figure 18
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Fig. 8B —34-year-old-woman with endobronchial schwannoma in bronchus intermedius. The patient had chronic cough, and sputum was present. Cut surface of resected lung specimen shows yellowish white endobronchial mass (black arrow) obstructing bronchus intermedius. Distal bronchi are dilated and filled with mucous plugs (white arrows).

 


Figure 19
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Fig. 8C —34-year-old-woman with endobronchial schwannoma in bronchus intermedius. The patient had chronic cough, and sputum was present. Scanning microscopic view shows mass (M) with intact overlying respiratory epithelium.

 


Figure 20
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Fig. 8D —34-year-old-woman with endobronchial schwannoma in bronchus intermedius. The patient had chronic cough, and sputum was present. High-power view shows fascicles of wavy nuclei with tapered ends and palisading consistent with schwannoma. (H and E x400)

 

Lipoma
Top
Abstract
Introduction
Hamartoma
Leiomyoma
Lipoma
Neurogenic Tumor
Inflammatory Polyp...
Amyloidoma
Papilloma
Pleomorphic Adenoma (Benign...
Other Benign Tumors
References
 
Tumors composed exclusively or almost exclusively of mature fat rarely occur within the lungs (0.1% of benign lung tumors) [1]. Intrathoracic lipomas are classified into five groups: endotracheobronchial, parenchymal, pleural, mediastinal, and cardiac. Most such neoplasms are endobronchial (Figs. 6A, 6B, and 6C). Tracheal lipoma is rare. In a review of reports, only three of 50 endobronchial lipomas were located in the trachea (Figs. 7A and 7B) [5].

Tracheobronchial lipoma arises from the submucosal fat of the tracheobronchial tree and usually is pedunculated with a narrow stalk. The tumor may extend between the cartilaginous rings into the peritracheal tissues and may recur after endoscopic resection.

Patients with tracheobronchial lipoma are generally in late middle age, and there is a definite male preponderance (ca. 90%). Lipoma, like other endobronchial tumors, produces symptoms and signs of obstruction, including productive cough, hemoptysis, wheezing, recurrent pneumonia, and bronchiectasis [1].


Figure 21
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Fig. 9A —65-year-old woman with endobronchial inflammatory polyp. The patient had had chronic cough. Contrast-enhanced CT scan shows low-attenuating endobronchial mass (arrow) obstructing right upper lobe bronchus.

 


Figure 22
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Fig. 9B —65-year-old woman with endobronchial inflammatory polyp. The patient had had chronic cough. Scanning microscopic view of excised polyp shows fibrovascular core lined by respiratory-type epithelium consistent with inflammatory polyp. (H and E, x1)

 


Figure 23
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Fig. 10A —50-year-old man with tracheobronchial amyloidosis and endobronchial amyloidoma. Contrast-enhanced CT scan shows nodular thickening of trachea and ovoid soft-tissue-density mass obstructing bronchus of right upper lobe.

 


Figure 24
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Fig. 10B —50-year-old man with tracheobronchial amyloidosis and endobronchial amyloidoma. Shaded-surface display 3D image shows multiple nodular indentations in tracheobronchial tree and occlusion of right upper lobe bronchus.

 
The chest radiographic features of lipoma are typically related to obstruction [1]. Bronchoscopy often does not provide enough information for a diagnosis because of the fibrous capsule surrounding the lesion. Bronchoscopic findings can be misleading because the simultaneous detection of atypical cells associated with chronic irritation and infection leads to an incorrect diagnosis of bronchogenic cancer.

CT is highly specific and sensitive in the detection of fat, and CT findings can lead to a definitive diagnosis of tracheobronchial lipoma (Figs. 6A, 6B, 6C, 7A, and 7B). However, endobronchial hamartoma also can appear as a fatty mass on CT [1]. Therefore, whenever a fatty endobronchial mass is identified on CT, the differential diagnosis should include lipoma and hamartoma. Whenever possible, the treatment of patients with tracheobronchial lipoma is laser resection by means of bronchoscopy.


Neurogenic Tumor
Top
Abstract
Introduction
Hamartoma
Leiomyoma
Lipoma
Neurogenic Tumor
Inflammatory Polyp...
Amyloidoma
Papilloma
Pleomorphic Adenoma (Benign...
Other Benign Tumors
References
 
Intrathoracic neurogenic tumors, schwannoma and neurofibroma, occur most often in the posterior mediastinum and only rarely in the lungs. In a large series of pulmonary neoplasms, neurogenic tumor constituted 0.2% of the tumors. According to results of most studies, neurofibroma is more common than schwannoma by a ratio of 3:1. Most neurogenic tumors are intraparenchymal and manifest as asymptomatic masses; however, 25% of tumors are endobronchial and often cause obstructive symptoms. Most tumors are solitary and not associated with Reckling-hausen's disease. The clinical course depends on tumor size and the degree of bronchial obstruction [1].


Figure 25
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Fig. 11A —48-year-old man with tracheal papillomatosis. CT scan at level of branch of brachiocephalic vessels shows small, well-defined nodule (arrow) in posterior wall of trachea.

 


Figure 26
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Fig. 11B —48-year-old man with tracheal papillomatosis. CT scan at level of aortic arch shows lobulating polypoid mass in posterior wall of trachea.

 


Figure 27
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Fig. 11C —48-year-old man with tracheal papillomatosis. Shaded-surface display 3D image of trachea shows irregular narrowing, secondary to nodular lesions with irregular surfaces.

 


Figure 28
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Fig. 11D —48-year-old man with tracheal papillomatosis. Histologic findings are proliferation of well-differentiated squamous epithelium with fibrovascular core. (H and E, x100)

 
The histologic findings of both schwannoma and neurofibroma are similar to those of their extrapulmonary counterparts. Schwannoma is encapsulated and has two patterns: Antoni type A (cellular pattern composed of compactly arranged spindle cells with elongated, wavy nuclei disposed in a parallel palisade arrangement) and Antoni type B (fewer cellular zones with elongated cells arranged in a haphazard pattern and separated by a poorly staining matrix). Neurofibroma is composed of haphazardly arranged spindle cells with wavy nuclei, eosinophilic cytoplasm, and variably collagenous and myxoid matrix. Schwannoma exhibits ultrastructural evidence of Schwann cell derivation, including prominent interdigitating cell processes, basal lamina, and Luse bodies. Both schwannoma and neurofibroma have positive results for S-100 protein [1].

Chest radiography shows that neurogenic tumor is typically related to endobronchial obstruction. A few surgical reports of endobronchial neurogenic tumors describe the tumors as round, ovoid, or lobulated and as sharply demarcated, homogeneous masses on CT (Figs. 8A, 8B, 8C, and 8D) [6]. Treatment is usually resection, either endoscopic or by thoracotomy. The prognosis is excellent in the absence of neurofibromatosis.


Inflammatory Polyp (Fibroepithelial Polyp)
Top
Abstract
Introduction
Hamartoma
Leiomyoma
Lipoma
Neurogenic Tumor
Inflammatory Polyp...
Amyloidoma
Papilloma
Pleomorphic Adenoma (Benign...
Other Benign Tumors
References
 
Inflammatory polyp typically occurs in the large airways. Many of these lesions are thought to be related to some form of underlying irritation or inflammatory process, including foreign body, inhalation of hot or corrosive gas, and, rarely, bronchiolitis. Removal of the causative factor often leads to regression of the polyp.


Figure 29
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Fig. 12A —68-year-old woman with endobronchial pleomorphic adenoma. Patient had had recurrent pneumonia and chronic cough for 4 years. CT scan shows low-attenuating endobronchial mass (arrow) and distal pneumonia.

 


Figure 30
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Fig. 12B —68-year-old woman with endobronchial pleomorphic adenoma. Patient had had recurrent pneumonia and chronic cough for 4 years. Endobronchial adenoma with juxtaposed, solid, cellular zones and myxoid stroma. Ductlike and solid myoepithelial component is adjacent to myxoid stromal component. (H and E, x200)

 
Radiographs may reflect the endobronchial obstruction caused by the polyp, and CT may elucidate the cause in the setting of a foreign body or broncholith (Figs. 9A and 9B). The histologic features of inflammatory polyp are similar to those of a skin tag and include a fibrovascular core lined by respiratory-type or metaplastic squamous epithelium [1].


Amyloidoma
Top
Abstract
Introduction
Hamartoma
Leiomyoma
Lipoma
Neurogenic Tumor
Inflammatory Polyp...
Amyloidoma
Papilloma
Pleomorphic Adenoma (Benign...
Other Benign Tumors
References
 
Amyloidosis includes several diseases characterized by the presence of extracellular deposits of the insoluble protein fibril amyloid that histochemically binds with Congo red, thus showing birefringence in polarized light. Primary amyloidosis of the lung was classified by Spencer [7] as follows: localized bronchial deposits, diffuse bronchial deposits, localized parenchymal deposits, and diffuse parenchymal deposits. Bronchial type amyloidosis occurs as an isolated mass or as a diffuse infiltration within the wall. Diffuse tracheobronchial amyloidosis is the most common form of primary lung amyloidosis. Radiologic findings of tracheobronchial amyloidosis reflect the pathologic findings and vary from a solitary mass to diffuse tracheal narrowing. CT shows nodules, plaques, or circumferential thickening of the trachea, main bronchus, and lobar and segmental bronchi with partial or complete luminal narrowing (Figs. 10A and 10B). Mural nodulation and calcification of the thickened tracheobronchial wall may be visible.


Papilloma
Top
Abstract
Introduction
Hamartoma
Leiomyoma
Lipoma
Neurogenic Tumor
Inflammatory Polyp...
Amyloidoma
Papilloma
Pleomorphic Adenoma (Benign...
Other Benign Tumors
References
 
Squamous cell papilloma is the most common benign tracheobronchial neoplasm. When it involves the tracheobronchial tree, this lesion has two forms: multiple and solitary [1]. The multiple form of airway papilloma, known as juvenile laryngotracheal papillomatosis, is a neoplastic growth secondary to infection with human papillomavirus types 6 and 11.

Solitary papilloma of the tracheobronchial tree is less common than the multiple form and usually occurs in adults. Unlike the multiple form, solitary papilloma is associated with cigarette smoking or arises de novo. Squamous cell papilloma usually is benign in children and may regress. In adults, however, this tumor can infiltrate and become malignant.

Gross examination shows papillomas are polypoid or sessile masses within the airways. The lesions are characterized histologically by a proliferation of well-differentiated squamous epithelium with a central fibrovascular core. Radiologic findings include polypoid intraluminal masses, atelectasis, and obstructive pneumonitis (Figs. 11A, 11B, 11C, and 11D). Involvement of the distal airway can produce pulmonary nodules that frequently have cavitations.


Pleomorphic Adenoma (Benign Mixed Tumor)
Top
Abstract
Introduction
Hamartoma
Leiomyoma
Lipoma
Neurogenic Tumor
Inflammatory Polyp...
Amyloidoma
Papilloma
Pleomorphic Adenoma (Benign...
Other Benign Tumors
References
 
Primary pulmonary tumors histologically similar to salivary gland tumors are exceedingly rare, and most are malignant. Of the benign bronchial gland tumors that mimic salivary tumors, the most common is probably pleomorphic adenoma (benign mixed tumor). Although it is the most common form of salivary gland tumor, pleomorphic adenoma is exceedingly rare in the lung [1].

Pulmonary pleomorphic adenoma has been reported in patients 11-74 years old, but it occurs most often in the sixth and seventh decades. The tumor occurs equally in men and women. Most tumors are polypoid endobronchial masses, but peripheral tumors do occur. Endobronchial lesions are often polypoid and exhibit some degree of luminal occlusion. The lesions are circumscribed, unencapsulated, and exhibit a grayish white, rubber or myxoid cut surface.

The CT finding in reported cases of pleomorphic adenoma was an endotracheal polypoid mass or mass in the peripheral aspect of the lung [8]. In our case, the adenoma was located within the apical segmental bronchus and caused recurrent pneumonia (Figs. 12A and 12B). The prognosis and behavior of pulmonary pleomorphic adenoma are similar to those of salivary gland pleomorphic adenoma. Circumscription and small size are associated with a benign course when this tumor is managed by lobectomy. Infiltrative or poorly circumscribed lesions are more likely to recur or metastasize [1].


Other Benign Tumors
Top
Abstract
Introduction
Hamartoma
Leiomyoma
Lipoma
Neurogenic Tumor
Inflammatory Polyp...
Amyloidoma
Papilloma
Pleomorphic Adenoma (Benign...
Other Benign Tumors
References
 
Benign tumors of the tracheobronchial tree not found among our cases include granular cell tumor, hemangioma, and fibroma. Granular cell tumors are uncommon benign neoplasms of neurogenic origin. Within the respiratory tract, the larynx is most frequently affected, followed by the bronchi. The trachea is rarely affected [9]. Approximated 2-6% of all granular cell tumors occur in the lung with equal sex incidence and at a median age of 40 years (range, 8-59 years) [1]. Chest CT is useful for identifying the endobronchial mass, but there are no specific imaging features for the diagnosis of granular cell tumor [1].

Hemangiomas in adults occur more commonly in the larynx. In children, they occur predominantly in the subglottic area [9]. The radiologic finding of subglottic hemangioma is a sharply marginated, rounded soft-tissue mass often associated with considerable airway narrowing [9].

Fibroma of the tracheobronchial tree is rare. In a study of 185 benign tumors of the tracheobronchial tree, 2.2% (4 cases) of the lesions were fibroma [10]. Tracheobronchial fibromas are histologically identical to localized fibrous tumors of pleura [11]. Like other benign mesenchymal tumors, tracheal fibroma appears as a round or oval, well-defined, submucosal mass with projection into the tracheal lumen [12].


Acknowledgments
 
We thank Bonnie Hami, Department of Radiology, University Hospitals of Cleveland, Cleveland, OH, for her editorial assistance in the preparation of the manuscript.


References
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Abstract
Introduction
Hamartoma
Leiomyoma
Lipoma
Neurogenic Tumor
Inflammatory Polyp...
Amyloidoma
Papilloma
Pleomorphic Adenoma (Benign...
Other Benign Tumors
References
 

  1. Wilson RW, Kirejezyk W. Pathological and radiological correlation of endobronchial neoplasm. Part I. Benign tumors. Ann Diagn Pathol 1997; 1:31 -46[CrossRef][Medline]
  2. Ahn JM, Im JG, Seo JW, et al. Endobronchial hamartoma: CT findings in three patients. AJR 1994;163 : 49-50[Free Full Text]
  3. Douzinas M, Sheppard MN, Lennox SC. Leiomyoma of the trachea: an unusual tumour. Thorac Cardiovasc Surg1989; 37:285 -287[Medline]
  4. Arrigoni MG, Woolner LB, Bernatz PE, Miller WE, Fontana RS. Benign tumors of the lung: a ten-year surgical experience. J Thorac Cardiovasc Surg 1970; 60:589 -599[Medline]
  5. Politis J, Funahashi A, Gehlsen JA, DeCock D, Stengel BF, Choi H. Intrathoracic lipomas: report of three cases and review of the literature with emphasis on endobronchial lipoma. J Thorac Cardiovasc Surg 1979; 77:550 -556[Abstract]
  6. Tsukada H, Osada H, Kojima K, Yamate N. Bronchial wall schwannoma removed by sleeve resection of the right stem bronchus without lung resection. J Cardiovasc Surg (Torino) 1998;39 : 511-513[Medline]
  7. Spencer H. Pathology of the lung, 4th ed. Oxford, UK: Pergamon Press, 1985:773 -779
  8. Noda M, Tabata T, Yamane Y. Pleomorphic adenoma of the lung: report of a case [in Japanese]. Kyobu Geka 2002;55 : 1073-1076[Medline]
  9. McCarthy MJ, Rosado-de-Christenson ML. Tumors of the trachea. J Thorac Imaging 1995;10 : 180-198[Medline]
  10. Shah H, Garbe L, Nussbaum E, Dumon JF, Chiodera PL, Cavaliere S. Benign tumors of the tracheobronchial tree: endoscopic characteristics and role of laser resection. Chest 1995;107 : 1744-1751[Abstract/Free Full Text]
  11. Yousem SA, Flynn SD. Intrapulmonary localized fibrous tumor: intraparenchymal so-called localized fibrous mesothelioma. Am J Clin Pathol 1988; 89:365 -369[Medline]
  12. Miller WT Jr. Obstructive diseases of the trachea. Semin Roentgenol 2001; 36:21 -40[CrossRef][Medline]

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