ChestPulmonary Tumors

Mohamed Zaitoun

Assistant Lecturer-Diagnostic Radiology Department , Zagazig University Hospitals

EgyptFINR (Fellowship of Interventional

Neuroradiology)-Switzerlandzaitoun82@gmail.com

Knowing as much as possible about your enemy precedes successful battle

and learning about the disease process precedes successful management

Pulmonary Tumors(i) Malignant Tumors(ii) Low-grade Malignancies(iii) Benign Tumors

(i) Malignant Tumors :1-Bronchogenic Carcinoma2-Bronchoalveolar Carcinoma (BAC)3-Lymphoma4-Metastases5-Sarcomas , rare

1-Bronchogenic Carcinoma :a) Classificationb) Risk Factorsc) Locationd) Radiographic Findingse) Paraneoplastic Syndromesf) TNM Staging

a) Classification :1-Adenocarcinoma (most common) , 40% 2-Squamous Cell Carcinoma , 30%3-Small Cell Carcinoma , 15% 4-Large Cell Carcinoma , 1%5-Adenosquamous tumor , rare

1-Adenocarcinoma (most common), 40% :-Now the most frequent primary lung cancer-Typically presents as a multilobulated

peripheral mass-May arise in scar tissue : scar carcinoma

Bronchioloalveolar Carcinoma (BAC ) :-Subtype of adenocarcinoma-Slow growth-Morphologic type :1-Small peripheral nodule (solitary form), 25%

(most common)2-Multiple nodules3-Chronic airspace disease-Air Bronchogram-Absent Adenopathy-Cavitation may be seen by HRCT (cheerio sign),

(pulmonary nodules with a central lucent cavity as seen on CT)

Cheerio sign

2-Squamous Cell Carcinoma (SCC) , 30% :-SCC is most directly linked with smoking-SCC carries the most favorable prognosis -The most characteristic radiographic appearances

are : a) Cavitating lung mass , 30%b) Peripheral nodule , 30%c) Central obstructing lesion causing lobar collapsed) Chest wall invasion

Pancoast Tumor (Superior Sulcus Tumor) :a) Definitionb) Clinical Picturec) Radiographic Findings

a) Definition :-Tumor located in the lung apex that has

extended into the adjacent chest wall-Histologically, Pancoast tumors are often

SCC

b) Clinical Picture :1-Horner syndrome2-Pain radiating into arm (invasion of

pleura , bone, brachial plexus or subclavian vessels)

c) Radiographic Findings :1-Plain Radiography :-Soft tissue opacity at the apex of the lung-Occasionally rib involvement or extension

into the supraclavicular fossa may be evident

-Lordotic views may be helpful

2-CT :-Apical mass-Chest wall invasion-Involvement of subclavian vessels-Brachial plexus involvement-Bone involvement : rib , vertebral body

3-Small Cell Carcinoma (Neuroendocrine Tumor Type 3) , 15% :

-Most aggressive lung tumor with poor prognosis-At diagnosis, two thirds of patients already have

extrathoracic spread-Typical initial presentation :a) Massive bilateral lymphadenopathyb) With or without lobar collapsec) Brain metastases-Central location

SCLC in a 65-year-old man who presented with cough and chest pain, (a) Well-collimated contrast-enhanced CT image (lung window) shows a large mass in the right upper lobe. Note the extensive centrilobular and paraseptal emphysema in the lungs, (b) Well-collimated contrast-enhanced CT image (soft-tissue window) shows hypoattenuation of the tumor, a finding that suggests necrosis, note also the enlarged right paratracheal lymph node (arrow), consistent with nodal disease, CT-guided biopsy revealed SCLC

SCLC in a 57-year-old man who presented with progressive weight loss, (a) PA chest radiograph shows marked thickening of the right paratracheal stripe (arrow), a finding that is suggestive of mediastinal lymphadenopathy or a mediastinal mass, (b) Well-collimated contrast-enhanced CT image shows a soft-tissue mass in the right mediastinum, no pulmonary lesions were identified at CT, Bronchoscopic biopsy revealed SCLC, which can manifest as a mediastinal mass or mediastinal lymphadenopathy with or without visualization of a primary lung tumor

SCLC in a 63-year-old woman, PA chest radiograph shows a well-defined nodule in the right lung (arrowhead), consistent with biopsy-proved SCLC, a convex opacity in the right paratracheal region (arrow) represents ipsilateral mediastinal lymphadenopathy

SCLC in a 54-year-old woman, CT+C shows a primary tumor in the middle to posterior mediastinum (*), invading the heart and resulting in atelectasis of the right lower lobe (arrow), a small right-sided pleural effusion is also seen (arrowhead)

Brain metastases, small cell carcinoma

4-Large Cell Carcinoma , 1% :-Usually presents as large (>70% are >4 cm at

initial diagnosis) peripheral mass lesions-Overall uncommon tumor5-Adenosquamous tumor , rare :-A carcinoma showing components of

adenocarcinoma and squamous cell carcinoma -Single peripheral lesion

b) Risk Factors :1-Smoking, more in Squamous cell

carcinoma followed by Adenocarcinoma2-Radiation3-Asbestos Exposure4-Genetic Predisposition

c) Location : (S is Central)1-Adenocarcinoma : Peripheral2-SCC : Central3-Small Cell Carcinoma : Central4-Large Cell Carcinoma : Peripheral 5-Adenosquamous : Peripheral

d) Radiographic Findings :*Primary Signs of Malignancy :1-Mass > 6 cm or nodule < 6 cm with

speculated irregular borders2-Unilateral enlargement of hilum3-Cavitation4-Chronic Airspace Disease5-Air Bronchograms

1-Mass > 6 cm or nodule < 6 cm with speculated irregular borders

a) A 55 yr old dyspnoeic female , chest radiograph shows widened mediastinum particularly on the right with reduced vascularity of the right lung

b) CT+C shows central mediastinal mass invading the right pulmonary artery , small cell carcinoma was confirmed on percutaneous biopsy

a) Rib erosion (large arrow) due to peripheral tumor (small arrows) suggesting at least T3 disease

b) Corresponding CT showing mass eroding rib and vertebral body (arrows) confirming T4 status and inoperability

Speculated margin

Corona radiata sign : highly associated with malignancy

Large central mass (arrows) narrowing left main bronchus and encasing left pulmonary artery , indicating T4 status

A pleural effusion is noted

SCLC resulting in mediastinal invasion, (a) PA chest radiograph shows a lobular masslike opacity (arrow) in the left perihilar and suprahilar lung, (b) CT+C shows a large soft-tissue mass invading the left mediastinum and surrounding and markedly narrowing the left upper lobe pulmonary artery (arrowheads)

 Frank chest wall invasion by large peripheral tumor

2-Unilateral enlargement of hilum :-Mediastinal widening , hilar prominence

Bronchogenic carcinoma is seen peripheral and in the upper lobes(black arrow) , note the right hilar lymphadenopathy (white arrow)

SCLC in a 63-year-old woman, PA chest radiograph shows a well-defined nodule in the right lung (arrowhead), consistent with biopsy-proved SCLC, a convex opacity in the right paratracheal region (arrow) represents ipsilateral mediastinal lymphadenopathy

Bronchial carcinoma in the posterior upper lobe on the left side, which lies next to the descending aorta , two lymph nodes are seen in the aortopulmonary window between the ascending aorta and the descending aorta , on the contralateral side there is a pretracheal-retrocaval lymph node

Mediastinal lymph nodes (arrow) and a necrotic tumor mass within the lung

3-Cavitation :-Most common in upper lobes or superior

segments of lower lobes-<4 mm : 95% of cavitated lesions are

benign->15 mm : 85% of cavitated lesions are

malignant-Cavitation is most common in squamous

cell carcinoma (SCC)

Cavitating Lung Tumor

Cavitating Lung Tumor

60-year-old man with newly diagnosed squamous cell carcinoma, CT+C reveals a 2.8 cm cavitary nodule (arrow) in the lower lobe of the right lung

-Irregular opacity (yellow dotted line) has a central air density lucency (red dotted line) with a horizontal inferior margin (blue arrows) consistent with an air-fluid level , indicative of cavitation

A 50 years old female with irregular cavitating squamous cell carcinoma in the right upper lobe (arrows)

4-Certain tumors may present as chronic airspace disease : bronchoalveolar carcinoma (BAC) & lymphoma

a) Diffuse alveolar shadowing in the right lower lobe of a 58 yr old male presenting as an unresolving pneumonia

b) Air bronchograms (black arrows) and low attenuation lucencies (open arrow) in apical “consolidation”, later confirmed as bronchoalveolar carcinoma

SCLC in a 58-year-old man with a history of nonresolving pneumonia of the right lung on serial radiographs and clinical symptoms of the syndrome of inappropriate antidiuretic hormone secretion, CT+C shows nonenhancing consolidation in the right upper lobe, note the enlarged lymph node (*) anterior to the carina, a finding that is consistent with nodal disease, Bronchoscopic biopsy revealed SCLC

5-Some air bronchograms are commonly seen by HRCT in adenocarcinoma

-Air bronchogram seen as a linear lucency (broad arrow) and as a more cystic lucency (small arrow) due to the fact that the bronchus is seen en face

Primary lung invasive mucinous adenocarcinoma in right upper lobe presenting as air-space consolidation with air bronchograms in 68-year-old man, ill-defined centrilobular nodules (arrows) with ground-glass attenuation are present posterior to lesion

*Secondary Signs of Malignancy :1-Atelectasis (Golden's inverted “S” sign in

RUL, LUL collapse)2-Obstructive pneumonia3-Pleural effusion & elevation of the diaphragm4-Interstitial patterns : lymphangitic tumor

spread5-Hilar and mediastinal adenopathy6-Metastases to ipsilateral , contralateral lung

Golden Sign

Right hilar mass (orange) obstructing the right upper lobe bronchus results in collapse of the right upper lobe (green arrow) , this results in a reverse S shape to the pleural edge

Collapsed right upper lobe with a convex bulge along the lower aspect of the collapsed lung (white arrows) producing a Golden 'S' sign

Right upper lobe collapse with a central mass (white arrow)

Central mass with Golden “S” sign of proximal tumor (arrows) and distal collapse

 a) Collapse of the left lung with mediastinal shift and a right middle zone nodule (arrow)

b) Perihilar low attenuation adenocarcinoma (arrows) with distal enhancing collapsed lung in same patient

Left hilar mass with loss of volume and/or post obstructive pneumonia in the left lower lobe

Chest CT scan shows a right upper lobe mass (arrow) with mediastinal and carinal invasion, ipsilateral loculated pleural effusion, and thickening and enhancement of the pleura, note the tumor encasement and resultant narrowing of the right main-stem bronchus (arrowhead), the pleural thickening and enhancement, although nonspecific, are suggestive of metastatic pleural disease

CXR shows a large opacity in the right upper zone consistent with collapse of the right upper lobe secondary to a hilar mass , note the hyperlucency of the hyperexpanded right lower and middle lobe and elevation of the right hemidiaphragm , either due to volume loss or less likely phrenic nerve paralysis

e) Paraneoplastic Syndromes :a) Metabolicb) Musculoskeletalc) Other

a) Metabolic :1-Cushing's syndrome (ACTH)2-Inappropriate antidiuresis (ADH)3-Carcinoid syndrome (serotonin , other

vasoactive substances)4-Hypercalcemia (PTH , bone metastases)5-Hypoglycemia (insulin-like factor)

b) Musculoskeletal :1-Neuromyopathies2-Clubbing of fingers (HPO)

c) Other :1-Acanthosis nigricans2-Thrombophlebitis3-Anaemia

2-Bronchioloalveolar Carcinoma (BAC) :a) Incidenceb) Clinical Picturec) Radiographic Findingsd) Differential Diagnosis

a) Incidence :-Sub-group of adenocarcinomas of the lung

accounting for 2-9% of primary lung lesions

-A disease presenting in the 6th and 7th decades with a 3:2 male predominance

b) Clinical Picture :-Nearly half of patients with BAC are asymptomatic

at presentation with cough , chest pain and weight loss most common among those with symptoms

-If the tumor is mucin secreting , a productive cough with abundant mucoid expectoration can be seen

-This classic finding of (marked) bronchorrhea is an uncommon and late finding

c) Radiographic Findings : 3 Patterns1-Solitary Nodule2-Consolidated Form3-Diffuse or Multicentric Form

1-Solitary Nodule :-Usually a well-circumscribed focal mass

located in the periphery of the lung with spiculated borders

-A pleural tag or "tail sign" is common and describes linear strands extending from nodule to pleura

Solitary peripheral nodule with pleural tags

Solitary peripheral nodule with bubblelike lucencies

2-Consolidated Form :-May be segmental or involve an entire lobe-The combination of growth along the air spaces

with the production of mucin may cause the features of airspace consolidation with air-bronchograms

-If a large amount of mucin is present it may cause consolidation of low attenuation and following the administration of I.V. , the vessels will be seen within the consolidation , this is referred to as the CT angiogram sign and is suggestive of BAC

-A characteristic finding of BAC is the presence of bubble like lucencies or pseudocavitation which corresponds to patent small bronchi or air-containing cystic spaces in papillary tumors

Isolated lobar consolidation with bulging of major fissure and cystic air spaces

Isolated lobar consolidation with the angiogram sign

3-Diffuse or Multicentric Form :-Widespread disease in multiple lobes of

both lungs*N.B. :-Classic radiographic findings in BAC

include a solitary spiculated mass with air bronchograms

-Airspace consolidation and a diffuse multicentric presentation are also common

Multinodular pattern with foci of calcifications within one of the nodules

Multinodular pattern with cavitation of some nodules

a) Solitary nodule , 2 cm , note the bubble like lucencies inside the nodule

b) Isolated lobar consolidation , 15 months later , note the angiogram inside the consolidation

c) Contralateral consolidation , 4 months later after left lower lobectomy

d) Differential Diagnosis :- Includes lymphoma and infectious

processes such as TB

3-Lymphoma :-See Mediastinum

-Differential Diagnosis of unilateral hilar enlargement :a) Lymph nodes :1-Lung cancer (hilar enlargement may be tumor itself or

malignant lymph nodes)2-Lymphoma (unilateral is unusual , involvement is usually

bilateral and asymmetrical)3-Infection :-Primary T.B.-Histoplasmosis-Coccidiodomycosis-Mycoplasma4-Sarcoidosis (unilateral is in only 1-5 %)

b) Pulmonary artery :1-Pulmonary embolus2-Aneurysm3-Post stenotic dilatationc) Others :1-Mediastinal mass (extending into the

hilum)2-Perihilar pneumonia

-Differential Diagnosis of bilateral hilar enlargement :a) Idiopathic :-Sarcoidosisb) Neoplastic :-Lymphoma (asymmetrical)-Lymphangitis carcinomatosisc) Infective :-Viruses (most commonly in children)-Primary T.B.-Histoplasmosis-Coccidiodomycosis

d) Vascular :-Pulmonary artery hypertensione) Immunological :-Hypersensitivity pneumonitis f) Inhalational :-Silicosis -Chronic berylliosis

-Differential Diagnosis of egg shell calcification of lymph nodes :

*Defined as shell like calcifications up to 2 mm thick in the periphery of at least two lymph nodes

1-Silicosis2-Coal Miner’s pneumoconiosis3-Sarcoidosis4-Lymphoma following radiotherapy*This should be differentiated from :-Pulmonary artery calcification-Aortic calcification-Anterior mediastinal tumors (Teratodermoid & thymomas

may have rim calcification)

4-Metastases :a) Pathways of metastatic spread from a primary

extrathoracic site to lungsb) Neoplasms with rich vascular supplyc) Neoplasms with lymphatic disseminationd) Other neoplasms with high propensity to

localize in lunge) Calcified Metastasesf) Giant Metastasesg) Sterile Metastases

a) Pathways of metastatic spread from a primary extrathoracic site to lungs :

1-Spread via pulmonary arteries2-Lymphatic spread (celiac nodes → posterior

mediastinal nodes + paraesophageal nodes) and in lung parenchyma

3-Direct extension4-Endobronchial spread

b) Neoplasms with rich vascular supply draining into systemic venous system :

1-Renal cell carcinoma2-Sarcomas3-Trophoblastic tumors4-Testis5-Thyroid

c) Neoplasms with lymphatic dissemination :

1-Breast (usually unilateral)2-Stomach (usually bilateral)3-Pancreas4-Larynx5-Cervix

d) Other neoplasms with high propensity to localize in lung :

1-Colon2-Melanoma3-Sarcoma

Miliary Mets

e) Calcified Metastases :-Calcifications in lung metastases are

observed in :1-Bone Tumor Metastases2-Mucinous Tumors3-Metastases After Chemotherapy

1-Bone Tumor Metastases :a) Osteosarcomab) Chondrosarcoma

2-Mucinous Tumors :a) Ovarianb) Thyroidc) Pancreasd) Colone) Stomach3-Metastases After Chemotherapy

Multiple subcentimeter calcified pulmonary nodules (mets , red arrows) , pleural effusion (blue arrows)

f) Giant Metastases : Cannon Ball1-Head and neck cancer2-Testicular and ovarian cancer3-Soft tissue cancer4-Breast cancer5-Renal cancer6-Colon cancer

g) Sterile Metastases :-This term refers to pulmonary metastases

under treatment that contain no viable tumor

-Nodules typically consist of necrotic and/or fibrous tissue

5-Sarcoma :a) Primary sarcomas of the thorax :-Rare-They occur in the lung, mediastinum, pleura, and

chest wall-The most common primary intrathoracic sarcomas:1-Angiosarcoma2-Leiomyosarcoma3-Rhabdomyosarcoma4-Mesothelioma (Sarcomatoid variant)

1-Angiosarcoma :-Although primary intrathoracic angiosarcomas are rare,

they are the most common primary cardiac sarcoma and the majority of primary right atrial masses are angiosarcomas

-Primary angiosarcomas also occur in the anterior mediastinum, typically without an obvious vascular origin

-At radiography, extracardiac mediastinal sarcomas manifest as large masses

-They are typically located in the anterior mediastinum-The attenuation at CT can be homogeneous but is more

often heterogeneous due to areas of hemorrhage, necrosis, and cyst formation

-At CT and MR imaging, cardiac angiosarcomas manifest as diffuse wall thickening or focal masses that typically involve the right atrium and enhance heterogeneously after intravenous administration of contrast material

-Primary pulmonary angiosarcomas usually manifest as multiple bilateral nodules

Mediastinal angiosarcoma in a 38-year-old man, (a) PA chest radiograph shows a mediastinal contour abnormality (arrows), (b) CT+C shows a large, homogeneous mediastinal mass (arrows) abutting the aorta (A) and superior vena cava (S), at exploratory thoracotomy, the mass did not arise from or involve the aorta and heart, and resection was performed, location in the anterior mediastinum and absence of an obvious vascular origin are typical of angiosarcomas

2-Leiomyosarcoma :-Primary leiomyosarcomas occur in the mediastinum, heart,

and lung-Although they are reported to arise from mediastinal

structures such as the esophagus or mediastinal vasculature, including the pulmonary artery and superior vena cava, most mediastinal tumors do not involve these structures

-At radiologic analysis, these neoplasms manifest in the lung as well-marginated smooth or lobular homogeneous nodules or large necrotic masses

-Mediastinal leiomyosarcomas are usually large neoplasms that are often heterogeneous in appearance due to necrosis or hemorrhage within the masses

-Because leiomyosarcomas of the pulmonary artery frequently grow within the lumen, they can be difficult to distinguish from pulmonary artery thrombi

-MR imaging can often be useful in establishing the diagnosis because leiomyosarcomas, unlike thrombi, enhance after intravenous administration of gadolinium contrast material   

Pulmonary leiomyosarcoma in a 62-year-old woman, (a) CT+C shows a large, heterogeneous lung mass that extends into the azygoesophageal recess and compresses and displaces the left atrium (LA), note the origin in the lung, the large size, and the heterogeneous attenuation, common features of leiomyosarcoma, (b) T1+C fat-saturated shows that the mass is heterogeneous, diffuse enhancement surrounds well-circumscribed areas of low signal intensity (arrows), which are consistent with cystic spaces, (c) Axial fast spin-echo T2-weighted MR image shows a fluid-fluid level (arrow), which is consistent with blood products within a cystic space

Pulmonary artery leiomyosarcoma in a 41-year-old man, (a) PA chest radiograph shows a sharply marginated, lobular left hilar mass (M), (b) CT+C shows that the mass is homogeneous, it fills the left main pulmonary artery and extends into the left upper and lower lobe pulmonary arteries (arrows), (c, d) T1 (c) and T1+C (d) show that the mass has high signal intensity with heterogeneous enhancement (arrows in d), slow flow around the periphery of the mass causes high signal intensity (arrowheads in d), because enhancement is useful in distinguishing a pulmonary artery mass from a thrombus, intravenous administration of gadolinium contrast material is recommended in cases in which the diagnosis is uncertain

3-Rhabdomyosarcoma :-Rare thoracic neoplasms that occur within the lung,

bronchi, mediastinum, heart, and chest wall-At radiologic analysis, rhabdomyosarcomas manifest as

masses that are often large and of variable attenuation due to necrosis and cystic components within the masses

-Cardiac tumors typically manifest at CT as low-attenuation masses within a cardiac chamber

-The signal intensity at MR imaging is variable; the tumors may be isointense to muscle or have heterogeneous signal intensity if there are cystic or necrotic components within the mass

-Chest wall masses are typically large and can be homogeneous or heterogeneous

-Masses can be confined to the muscle of origin, although focal invasion is common

Rhabdomyosarcoma in a 42-year-old man, (a) PA chest radiograph shows a well-circumscribed mass in the right hemithorax that arises from the mediastinum, note the small right pleural effusion and the surgical clips from incisional biopsy, (b) CT+C shows that the mass is large and compresses the superior vena cava (arrow), note the heterogeneous attenuation within the mass, which is consistent with necrosis

4-Mesothelioma (Sarcomatoid variant) :-Sarcomatoid mesothelioma, a pleural malignancy

associated with exposure to asbestos-At radiologic analysis, sarcomatoid mesotheliomas

typically manifest as unilateral, lobular pleural masses that encase the hemithorax

-Most patients have an ipsilateral pleural effusion that can be small to large in volume

-Rarely, sarcomatoid mesotheliomas manifest as large, solitary masses

-This manifestation is less common in the epithelioid subtype of mesothelioma

-The mass can directly involve the adjacent lung or chest wall, mediastinal adenopathy and, less commonly, pulmonary metastases occur as late manifestations

-CT and MR imaging are optimal in assessing the extent and degree of invasion of adjacent structures

-At MR imaging, the tumor is usually isointense to slightly hyperintense (compared with muscle) on T1 and hyperintense on T2

Sarcomatoid mesothelioma in a 37-year-old man, (a) PA chest radiograph shows a focal extraparenchymal mass (arrows), note the bullous changes and scarring in the upper lobes, (b, c) T1 (b) and T1+C (c) show that the mass has intermediate signal intensity (similar to that of muscle) and heterogeneous enhancement, note the chest wall invasion (arrowheads)

b) Sarcomas with a Predominantly Chest Wall Location:

1-Ewing sarcoma :-Chest wall mass associated with bone

destruction)2-Primitive neuroectodermal tumors (Askin

Tumors) :-Chest wall masses that can be associated with

adjacent rib destruction, pleural thickening or pleural effusion, and focal invasion of lung

Ewing sarcoma in a 9-year-old boy, (a) PA chest radiograph shows a large mass within the left hemithorax that extends into the right hemithorax, (b) Nonenhanced CT shows that the mass is large and heterogeneous, there is destruction and inward displacement of a left rib (long arrow), rib destruction is typical but may not be extensive, note the local invasion into the subcutaneous tissues (short arrow). (c-e) Axial fast spin-echo T2 (c), coronal T1-weighted (d), and coronal T1+C  (e) show focal areas of high signal intensity and heterogeneous enhancement, findings consistent with necrosis and hemorrhage, note the marked displacement of mediastinal structures into the right hemithorax. LV = left ventricle

Primitive neuroectodermal tumor in a 44-year-old man, (a) PAchest radiograph shows a large, right-sided chest mass, (b) Nonenhanced CT scan shows that the mass is heterogeneous, note the absence of rib destruction, Primitive neuroectodermal tumors are typically located in the chest wall and demonstrate rib destruction less commonly than does Ewing sarcoma

3-Chondrosarcoma :-The most common primary malignancy of the

chest wall-Chondrosarcomas are typically located anteriorly

within the chest wall, arising from the sternum or costochondral arches

-Manifest as large chest wall masses with bone destruction and soft-tissue involvement. Scattered areas of calcification can occur in the chondroid matrix and are optimally detected with CT

Chest wall chondrosarcoma in a 62-year-old man, nonenhanced CT shows a large mass that arises from the costochondral junction, the mass extends into the subcutaneous tissue and compresses and displaces the heart, note the focal punctate and linear calcifications, anterior location, origin from the costochondral arches, and chondroid calcification are characteristic of chondrosarcomas of the chest wall

4-Malignant Fibrous Histiocytoma :-The most common soft-tissue sarcoma in adults, although

thoracic origin is infrequent-Well-marginated, smooth or lobular, soft-tissue chest wall

mass, CT usually reveals heterogeneous attenuation and enhancement   

5-Osteosarcoma :-Rare-The tumors typically arise from a rib, the scapula, or the

clavicle, at radiologic analysis, they manifest as bone destruction with an associated soft-tissue mass

-CT and MR imaging usually show a large mass that is typically heterogeneous in appearance because of necrosis, hemorrhage, and ossification, although all osteosarcomas contain osteoid matrix at histologic analysis, ossification may not be radiologically visible in some patients

Malignant fibrous histiocytoma of the chest wall in a 76-year-old woman, (a) PA chest radiograph shows a large extraparenchymal mass in the right upper hemithorax (arrowheads) with associated rib fractures and rib destruction (arrows), note the left pleural effusion, (b-d) T1 (b), T1+C (c), and fat-saturated T2 (d) show that the mass has heterogeneous signal intensity and marked enhancement, focal areas of low signal intensity on the T1 (arrow in b and c) have high signal intensity on the T2 (arrow in d) and are consistent with necrosis and fluid, origin within the chest wall musculature helps distinguish this tumor from osteosarcoma or chondrosarcoma

Osteosarcoma in a 43-year-old man, CT+C shows a left-sided chest wall mass with an osteoid matrix (arrow), a finding characteristic of chest wall osteosarcoma

Osteosarcoma in a 52-year-old woman, CT+C shows a heterogeneous chest wall mass without an ossified matrix

6-Synovial Sarcoma :-Typically occur as chest wall masses, although

they can (rarely) arise in the lung and pleura-At radiologic analysis, synovial sarcomas typically

manifest as heterogeneous masses that occasionally contain calcium, at MR imaging, these tumors demonstrate heterogeneous signal intensity on T1 and T2 and may have fluid-fluid levels due to hemorrhage and necrosis within cystic components of the tumor

Pulmonary synovial sarcoma in a 63-year-old man with pneumonia. (a) PA chest radiograph shows a mass in the right cardiophrenic angle (arrows) and heterogeneous areas of increased opacity in the middle and right lower lobes, findings consistent with pneumonia, (b) CT+C shows that the mass is heterogeneous, areas of low attenuation within the mass are consistent with extensive necrosis, note the small right pleural effusion

7-Fibrosarcoma :-Arise in the chest wall, mediastinum, heart, and lungs, in

the thorax, fibrosarcomas usually occur in the soft tissues of the chest wall

-At radiologic analysis, fibrosarcomas in the chest wall and heart usually manifest as masses that are often heterogeneous in attenuation and signal intensity on CT and MR images, respectively, due to internal necrosis and hemorrhage

-In the lung, fibrosarcomas manifest as well-marginated, smooth or lobular nodules or masses.

-At CT, these lesions are often nonspecific homogeneous nodules without calcification or ossification

-Endobronchial tumors can manifest as atelectasis or postobstructive pneumonitis

Fibrosarcoma of the breast in a 55-year-old woman, CT+C shows a focal, well-circumscribed mass in the left breast (arrow), the central area of low attenuation is suggestive of necrosis; the presence of necrosis was confirmed at resection

8-Neurofibrosarcoma :-Thoracic neurofibrosarcomas (also called malignant

peripheral nerve sheath tumors or malignant schwannomas) usually arise in preexisting neurofibromas of the intercostal nerves or spinal nerve roots or in the brachial plexus

-Usually of variable signal intensity on T1 and T2-Imaging features suggestive of malignant degeneration of a

benign neurogenic tumor to neurofibrosarcoma include a sudden increase in size or development of heterogeneous attenuation at CT due to internal necrosis and hemorrhage

-The development of heterogeneous signal intensity on T2 with loss of the peripherally hyperintense and centrally hypointense appearance (target sign) that is characteristic of neurofibromas is indicative of malignant transformation

Neurofibrosarcoma in a 33-year-old woman with type 1 neurofibromatosis, (a) Nonenhanced CT scan shows a large, homogeneous mass in the left axilla (arrows), note the absence of rib destruction, (b, c) Coronal T1 (b) and fat-saturated T2 (c) show that the mass (M) is well circumscribed with low signal intensity on the T1 (b) and high signal intensity on the T2 (c), note the small neurofibroma with similar signal intensity in the lower lateral aspect of the left hemithorax (arrow), the patient presented with pain in the region of the left axillary mass; because the characteristic appearance of a neurofibroma on T2 (the target sign) was absent, biopsy was performed

9-Undifferentiated or Spindle Cell Sarcomas :-High-grade or poorly differentiated sarcomas are

sarcomas that cannot be specifically classified histologically, these are termed undifferentiated sarcomas or spindle cell sarcomas

-At radiologic analysis, undifferentiated sarcomas tend to be large and can contain calcifications when there is a large component of myxoid matrix

-The masses typically have heterogeneous attenuation at CT and heterogeneous signal intensity on T1 and T2

Diaphragmatic undifferentiated sarcoma in a 48-year-old man, (a) PA chest radiograph shows a left pleural effusion, note the metastatic pulmonary nodule (short arrow) and the adenopathy in the aortopulmonary window (long arrow), (b) CT+C shows a large, heterogeneous mass with focal punctate calcifications (arrows), the resected specimen had a large component of myxoid matrix, which can result in intratumoral calcification

f) TNM Staging :-The current 7th edition NSCLC (Non-Small

Cell Lung Cancer) staging is as follow : 1-Primary tumor (T) 2-Nodal Staging (N)3-Metastases (M)

1-T-staging descriptor :-The parameter assessed on the T stage include

size , endobronchial location , local invasion , atelectasis and separate tumor nodules

*Tx :-Malignant cells on cytology but no tumor found on

bronchoscopy or imaging *Tis :-Carcinoma in situ

*T1 :T1a : Smaller than 2cm in longest dimensionT1b : Larger than 2cm but smaller or equal

to 3cm

Stage T1 tumors, (a) Chest CT scan shows a left lower lobe nodule (arrow) measuring less than 2 cm in size, a finding that is consistent with a stage T1a tumor (≤2 cm), (b) Chest CT scan obtained in a different patient shows a right upper lobe nodule (arrow) measuring 2.9 cm in size, a finding that is consistent with a stage T1b tumor (>2 cm but ≤3 cm)

*T2 :-> 3cm in size and > 2cm from carina ,

visceral pleura involvement , lobar atelectasis

T2a :-Larger than 3cm but smaller than 5cm-T2b :-Larger than 5cm but smaller than 7cm

Stage T2 tumors, (a) Chest CT scan shows a centrally located lung nodule (arrow) causing airway obstruction, with atelectasis or postobstructive pneumonia that does not, however, involve the entire lung, (b) Chest CT scan obtained in a different patient shows a mass in the right lung (arrow) measuring 4.8 cm, a finding that is consistent with a stage T2a tumor (>3 cm but ≤5 cm), (c) Coronal chest CT scan obtained in a third patient shows a nodule in the bronchus intermedius (arrow), the nodule is 4 cm from the carina (an endobronchial lesion > 2 cm from the carina is considered stage T2), at histopathologic analysis, the nodule proved to be a squamous cell carcinoma

*T3 :-< 2cm from carina but not involving trachea

or carina , involvement of chest wall , diaphragm , mediastinal pleura or parietal pericardium , separate tumor nodule(s) in the same lobe

*T4 :-Involvement of the trachea, esophagus ,

vertebra , great vessels or heart-Separate tumor nodules in the same lung

but not in the same lobe

Stage T3 tumors, (a) Chest CT scan shows an irregular mass in the left upper lobe with suspicious local extension to the mediastinal pleura (arrow), a finding that was subsequently confirmed at surgery and histopathologic analysis, (b) Chest CT scan obtained in a different patient shows an endobronchial mass (arrow) less than 2 cm from the carina. Pathologic analysis confirmed malignant carcinoid tumor, which can be staged using the 7th edition of the TNM staging system, (c) Chest CT scan obtained in a third patient shows a left lower lobe mass over 7 cm in diameter (arrow)

Stage T4 tumors, Chest CT scan shows a primary lung tumor in the right upper lobe (long arrow) with a smaller separate nodule in the right lower lobe (short arrow), in the 7th edition, this is considered stage T4 disease (stage M1 [metastatic] disease in the 6th edition

Stage T4 tumors, Chest CT scan shows a right upper lobe mass (arrow) with mediastinal and carinal invasion, ipsilateral loculated pleural effusion, and thickening and enhancement of the pleura, note the tumor encasement and resultant narrowing of the right main-stem bronchus (arrowhead), the pleural thickening and enhancement, although nonspecific, are suggestive of metastatic pleural disease, in the 7th edition, proved pleural carcinomatosis is considered stage M1a disease (stage T4 in the 6th edition)

2-Nodal Staging (N) :*Nx :-Regional nodes cannot be assessed*N0 :-No regional nodal metastases*N1 :-Ipsilateral peribronchial , hilar or

intrapulmonary nodes

Stage N1 lymph nodes, (a) Chest CT scan obtained in a patient with right-sided lung cancer shows an enlarged right hilar lymph node (level 10) (arrow) measuring 15 mm in the short axis, (b) Chest CT scan obtained in a different patient shows a left lower lobe mass and an ipsilateral enlarged interlobar lymph node (level 11) (arrow) measuring 11 mm in the short axis

*N2 :-Ipsilateral mediastinal or subcarinal nodes*N3 :-Contralateral nodal involvement , ipsilateral

or contralateral scalene or supraclavicular nodal involvement

Stage N2 lymph nodes, (a) Chest CT scan shows an enlarged (1.6-cm) right upper paratracheal lymph node (level 2) (arrowhead), (b) Chest CT scan obtained in a different patient shows an enlarged (1.5-cm) right lower paratracheal lymph node (level 4) (arrowhead), like the lymph node in a, it is clearly to the right of the new border proposed by the IASLC (ie, the left lateral border of the trachea), (c) Chest CT scan obtained in a third patient shows a right lower lobe mass (white arrow) with an enlarged (1.6-cm) subcarinal lymph node (level 7) (black arrow)

Stage N3 lymph nodes, (a) Axial PET/CT image of the chest shows a primary mass in the left lung (arrow) and a right lower paratracheal lymph node (arrowhead), both of which demonstrate intense radiotracer uptake. Metastatic involvement of the lymph node was confirmed at mediastinoscopic resection, (b) Chest CT scan obtained at the lung apex in a different patient shows enlarged bilateral supraclavicular lymph nodes (arrows), metastatic involvement was confirmed at excisional biopsy

3-Metastases (M) :*Mx :-Distant metastases cannot be assessed*M0 :-No distant metastases*M1 : M1a & M1b-Distant metastases present

*M1a :-Presence of a malignant pleural effusion ,

pleural dissemination or pericardial disease , intra thoracic metastases (metastasis in opposite lung)

*M1b :-Extra-thoracic metastases

Metastatic disease as seen at conventional imaging. (a) T1+C of the brain obtained in a patient with known primary lung cancer shows a ring-enhancing lesion with surrounding edema in the right occipital pole (arrow), a finding that is consistent with metastasis, (b) Abdominal CT scan obtained in a different patient shows multiple enhancing hepatic masses (arrows) and a right adrenal mass (arrowhead), findings that are consistent with metastatic disease, (c)Technetium-99m methylene diphosphonate nuclear bone scintigrams obtained in a third patient with lung cancer show multifocal areas of abnormal radiotracer uptake in the axial and appendicular skeleton, findings that are consistent with metastases

Separate tumor nodules, Chest CT scan shows a primary mass in the left lung (arrow) with a separate nodule in the right lung (arrowhead). This is stage M1a disease according to the 7th edition (stage M1 in the 6th edition) and involves intrathoracic spread rather than spread to distant extrathoracic sites

(ii) Low-grade Malignancies :1-Carcinoid , 90%2-Adenoid Cystic Carcinoma , 6%3-Mucoepidermoid Carcinoma , 3%4-Pleomorphic Carcinoma , 1%

Carcinoida) incidenceb) Typesc) Radiographic Featuresd) Neuroendocrine Tumors of the Lung

a) Incidence :-Represent 90% of low-grade malignancy

tumors of the lungb) Types :1-According to Histology2-According to Location

1-According to Histology :a) Typical Carcinoid :-Commoner -Low grade / well differentiated b) Atypical Carcinoid :-Less well differentiated-More aggressive

2-According to Location :a) Bronchial carcinoid tumors : central

lesionsb) Peripheral pulmonary carcinoid tumors :peripheral lesions

c) Radiographic Features :1-Centrally located carcinoid , 80% :-Endobronchial mass-Segmental or lobar collapse (most common

finding)-There is often marked homogeneous

contrast enhancement due to high vascularity

CXR shows complete collapse of the left lower , CT shows a hyperattenuating nodule (126 HU) within the left main bronchus

 Asymmetry of the bronchovascular bundles in the apex of the upper lobe , these are due to a small subtle hyperattenuating peripheral solitary pulmonary nodule immediately adjacent to the apical segmental bronchus of the right upper lobe , this finding is consistent with a primary bronchial carcinoid tumor

2-Peripherally located carcinoid, 20% :-Pulmonary nodule range around 10-30mm -May enhance with contrast

(iii) Benign Tumors (Rare) :1-Hamartoma2-Papilloma3-Leiomyoma4-Hemangioma5-Chemodectoma6-Pulmonary Blastoma7-Chondroma8-Multiple pulmonary Fibroleiomyomas9-Pseudolymphoma

Hamartomaa) Incidenceb) Locationc) Associationd) Radiographic Featurese) Differential Diagnosis

a) Incidence :-A benign neoplasm composed of cartilage ,

connective tissue , muscle , fat & bone-It is one of the commonest benign tumors of the

lung and accounts for approximately 8 % of all lung neoplasms and 6 % of solitary pulmonary nodules

-Usually present in the 4th and 5th decades of life -Usually discovered incidentally

b) Location :-90% are peripheral-10% are endobronchial

c) Association :-An unusual association is

with Gastrointestinal stromal tumors (GIST) and extra-adrenal paragangliomas This is known as the Carney triad 

d) Radiographic Features : Calcification & Fat1-Plain Film :- Soft tissue attenuation well-circumscribed mass

with either smooth or lobulated margins-Calcification (classically popcorn type) may be

seen (5-50 %)-Fat is difficult to identify with certainty (60 %) -Size is variable and they can be large (>10cm) but

in most cases they are less than 2.5 - 4 cm in diameter

2-CT :-They are typically well-circumscribed

nodules or masses (usually small) with either smooth or lobulated margins

-Approximately 60% have fat and approximately 20-30% have calcification / ossification (pop-corn like) 

-Calcification (popcorn configuration) -Fat can be recognized by comparing it to

subcutaneous fat and will typically have a Hounsfield measurement of -40 to -120HU

e) Differential Diagnosis :1-If fat is visualized then the differential is narrow

with almost all cases representing pulmonary hamartoma , See “Differential of fat containing solitary pulmonary nodule”

2-Presence of calcification also significantly narrows the differential but to a lesser degree , See “Differential of a solitary pulmonary nodule with calcification”

3-If neither fat nor calcification is present , then the differential is that of a solitary pulmonary nodule and is significantly broader , see “Differential of a solitary pulmonary nodule”

Imaging of Primary Chest Wall Tumors

a) Bone Tumorsb) Soft Tissue Tumorsc) Vascular Tumorsd) Peripheral Nerve Sheath Tumorse) Cutaneous Lesionsf) Fibroblastic Myofibroblastic Tumors

a) Bone Tumors :1-Bone Metastases (most common particularly in

older patients)2-Malignant Bone Tumors :-Chondrosarcoma is the most common primary

malignant bone tumor of the chest wall-Myeloma being the second most common-Ewing sarcoma is the most common primary bone

tumor in children

3-Benign Tumors :-Fibrous Dysplasia (the most common)-Osteochondroma-Enchondroma-Chondroblastoma-ABC-GCT-LCH

b) Soft Tissue Tumors :1-Lipoma (most common benign in adults)2-MFH (most common malignant in adults)3-Liposarcoma (2nd most common malignant

in adults)4-Rhabdomyosarcoma and primitive

neuroectodermal tumor “Askin tumor” (most common malignant soft-tissue tumors in children)

c) Vascular Tumors :1-Hemangioma2-Lymphangioma3-Hemangioendothelioma4-Angiosarcoma

d) Peripheral Nerve Sheath Tumors :1-Schwannoma2-Neurofibroma3-Malignant PNST

e) Cutaneous Lesions :1-Epidermal Inclusion Cyst (hypo in T1 , hyper in

T2 with peripheral rim of enhancement)2-Pilomatricoma :-Arise from hair matrix and are most commonly

found in children and young adults3-Dermatofibrosarcoma Protuberans (DFSP) :-Rare

f) Fibroblastic Myofibroblastic Tumors :1-Elastofibroma Dorsi2-Fibromatosis