GENERAL IMAGING FINDINGS:
The diagnosis of LFTP is important because the tumor is potentially resectable for cure despite its typically large size.
Normally,
LFTP is discovered incidentally on chest radiographs.
Findings from computed tomography (CT) scanning and magnetic resonance imaging (MRI) can suggest the diagnosis of LFTP.
However,
histopathologic examination is needed for a definitive diagnosis.
CHEST RADIOGRAPHY:
In most patients,
an LFTP is detected as an incidental finding on a chest radiograph,
appearing as a well-circumscribed,
homogeneous soft-tissue mass that is related closely to the pleura.
The lesion can arise anywhere along the pleura and can even be seen in the pulmonary fissures or along the mediastinal or diaphragmatic pleura.
This tumor presents as a pleural based mass and tends to be relatively circumscribed and can sometimes be lobulated.
Pedunculated lesions can change position and appearance with respiration or with a change in position (on serial radiographs).
Calcification,
rib destruction,
and pleural effusions are typically not associated features
The classic radiographic findings of pleural or extrapleural masses may be identified.
These include incompleta visualization of the tumor margins and sharp delineation of the mass on tangential images.
The size may range from less than 1.5cm to 25cm.
Tumors arising as a parietal chest wall mass typically produce at least one obtuse angle with the pleural surface.
Unfortunately,
only one third of the parietal pleural-based masses demonstrated an obtuse angle.
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/360857?maxheight=300&maxwidth=300)
Fig.: Benign LFTP in an asymptomatic 42-year-old man.
Posteroanterior chest radiograph shows a mass with sharp, smooth margins in the right hemithorax. The angle between the lesion and the chest wall is obtuse.
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/360983?maxheight=300&maxwidth=300)
Fig.: Contrast-enhanced computed tomography (CT) scan (mediastinal window) demonstrates a homogeneus lobular soft-tissue mass in the right hemithorax adjacent to the pleura(same patient as in the previous image).
LFTP may exhibit slow growth over time and may reach enormous sizes.
Pleural effusion is rare and may obscure a lesion in the inferior hemithorax.
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/362429?maxheight=300&maxwidth=300)
Fig.: LFTP in a 69-years-old man with dysnea grade II. PA chest radiograph demonstrates an enormous mass that occupies almost entire left hemithorax and produces mass effect on the mediastinum.
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/362492?maxheight=300&maxwidth=300)
Fig.: Contrast-enhanced chest CT scan (mediastinal window) demonstrates the large heterogeneously enhancing mass in the left hemithorax. Pleural effusion is associated (in the same patient as in the 2 previous image).
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/362495?maxheight=300&maxwidth=300)
Fig.: Contrast-enhanced CT scan shows a massive tumor occupying most of the left hemithorax, producing mass effect on the mediastinum and diaphragm (in the same patient as in the 3 previous image).
COMPUTED TOMOGRAPHY:
The chest computed tomography (CT) scan is the key examination,
which more clearly shows the size and location of the tumor and aids in surgical planning.
Both the benign and malignant varieties of SFTP usually appear as well-delineated,
soft-tissue-attenuating mass abutting the pleura,
with a round or lobulated contour that are usually heterogenous in attenuation.
Most SFTPs arise from the visceral pleura and half are pedunculated. The detection of a pedicle or a change in the lesion's position is suggestive of an LFTP.
Some tumors are located in the interlobar fissures,
and the occasional tumor appears to grow into the lung parenchyma,
the so-called “inverted” tumor,
which usually requires major lung resection for removal.
On contrast-enhanced CT scans,
the lesion enhances more than the soft tissue does,
because of its rich vascularization. Nonenhancing areas within the mass are correlated with the presence of necrosis,
hemorrhage,
or areas of myxoid or cystic degeneration.
Areas of low attenuation can be seen within an LFTP,
especially when the lesion is large.
A small,
ipsilateral pleural effusion can be seen. Areas of calcification are present in up to 26% of tumors.
The lesion displaces the adjacent mediastinum and lung parenchyma,
resulting in atelectasis.
Large lesions can compress adjacent vascular structures or bronchi.
Rarely,
chest wall invasion or rib notching can be seen.
The malignant form of LFTP cannot be confidently differentiated from the benign form by imaging.
Nevertheless,
malignant lesions are typically larger than 10 cm and are more likely to be associated with central necrosis and a large pleural effusion.
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/362740?maxheight=300&maxwidth=300)
Fig.: Unenhanced chest CT (mediastinal window)in a 78-year-old woman with constitutional syndrome. CT scan demonstrates a large mass in left hemithorax.
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/362769?maxheight=300&maxwidth=300)
Fig.: Contrast-enhanced CT demonstrates a large left-sided mass, displacing the mediastinum contralaterally, which contains “geographic” areas of low attenuation, within a large fibrous tumor of pleura. These areas correspond to necrosis (in the same patient as in the previous image).
Manifestations of LFTP on CT scans are usually not pathognomonic,
although some CT findings are highly suggestive of the diagnosis.
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363482?maxheight=300&maxwidth=300)
Fig.: Posteroanterior chest radiograph in a 77-years-old woman with pain in left hemithorax and weight loss. The radiography shows a mass in the lower left hemithorax.
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363490?maxheight=300&maxwidth=300)
Fig.: Lateral chest radiograph in the same patient as in the previous image.
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363494?maxheight=300&maxwidth=300)
Fig.: Contrast-enhanced computed tomography (CT) scan demonstrates a heterogeneously enhancing soft-tissue giant mass on the left hemithorax (in the same patient as in the previous 2 image).
No evidence of chest wall invasion is seen.
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363509?maxheight=300&maxwidth=300)
Fig.: Contrast-enhanced CT scan (mediastinal window) demonstrates extension of the mass to the abdominal cavity (same patient as in the previous 3 images)
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363552?maxheight=300&maxwidth=300)
Fig.: Posteroanterior chest radiograph in an asymptomatic 45-year-old woman.
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363553?maxheight=300&maxwidth=300)
Fig.: Lateral chest radiograph demonstrates a small lower thoracic mass(same patient as in the previous image).
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363554?maxheight=300&maxwidth=300)
Fig.: Sagittal reconstruction of contrast-enhanced chest CT scan shows a solid mass at the base of the left hemithorax(same patient as in the previous 2 images).
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363556?maxheight=300&maxwidth=300)
Fig.: Contrast-enhanced chest CT scan in a 45-year-old woman who presented noncalcified soft-tissue mass with smooth, lobulated margins (same patient as in the previous 3 images). The mass enhances slightly more than the soft tissue of the chest wall. No evidence of chest wall invasion is seen.
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363881?maxheight=300&maxwidth=300)
Fig.: Contrast-enhanced chest CT scan (lung window) shows the lesion located in the left lower lobe.
MAGNETIC RESONANCE IMAGING (MRI):
MRI is occasionally useful in evaluating potential invasion of the chest wall by a sessile tumor.
MRI with its sagittal and coronal views can help to clarify the tumor’s relationship to the diaphragm.
Spin-echo,
T1-weighted MRI scans predominantly demonstrate low to intermediate signal intensity,
and T2-weighted images depict low signal intensity.
The low intensity is attributed to the presence of fibrous,
hypocellular tissue.
Foci of increased signal intensity can be seen on T2-weighted images.
These foci correspond to the regions of decreased attenuation on CT scans and represent areas of necrosis,
hemorrhage,
or degeneration.
Intense enhancement is seen on gadolinium-enhanced T1-weighted images.
MRI machines can produce multiplanar images,
and MRI has superior tissue characterization compared with that of CT scanning; therefore,
MRI is helpful in evaluating an LFTP and in defining its pleural origin and extension.
After excluding calcifications,
the presence of low signal intensity on T1- and T2-weighted images is highly suggestive of the fibrous nature of the lesion.
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363966?maxheight=300&maxwidth=300)
Fig.: 45-year-old woman with dyspnea, cough and left-sided chest pain.
Posteroanterior chest radiograph demonstrates a superior hemithorax opacity and mediastinal displacement to the right.
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363978?maxheight=300&maxwidth=300)
Fig.: Coronal reconstruction of contrast-enhanced CT scan shows a massive tumor occupying most of the left hemithorax, producing mass effect on the mediastinum (same patient as in the previous image).
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363982?maxheight=300&maxwidth=300)
Fig.: Sagittal reconstruction of a contrast-enhanced CT scan demonstrates a large mass elongating supra-aortic trunks(same patient as in the previous 2 images)
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363984?maxheight=300&maxwidth=300)
Fig.: Contrast-enhanced computed tomography (CT) scan demonstrates a heterogeneously enhancing soft-tissue giant mass on the left hemithorax, displacing the mediastinum contralaterally, which contains “geographic” areas of low attenuation.Collateral circulation was visualized in the anterior mediastinum.(same patient as in the previous 3 images)
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363986?maxheight=300&maxwidth=300)
Fig.: Coronal gadolinium-enhanced T1-weighted MRI demonstrates a large mass in the left hemithorax. A significant associated mediastinal shift is seen, with no chest wall invasion.(same patient as in the previous 4 images)
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363997?maxheight=300&maxwidth=300)
Fig.: Cross-sectional MR image shows the tumor to be predominantly of low T2 signal intensity, containing a few high signal areas and necrosis. Absence of invasion of the spinal canal was demonstrated(in the same patient as in the previous image).
![](https://epos.myesr.org/posterimage/esr/ecr2011/107788/media/363999?maxheight=300&maxwidth=300)
Fig.: Angiography in the same patient as in the previous image. The right hemithorax mass demonstrates increased vascularity.