History :
The 60-year-old male was suffered from exertional dyspnea for 1 month.

Image finding :
-Diffuse thickening and tumor infiltration of pleural space of right lung.
-The tumor shows marked thickening of pleura and nodular appearance as well as mass infiltration.
-There is compression of right lung associated with irregular lung surface.
-Tumor involvement of the lung parenchyma esp. at right middle lobe and right lower lobe is noted.
-There is encasement of RULB,right intermedial bronchus and obstruction of RMLB and RLLB. Mild air bronchogram of collapse RLL is noted.
-The picture is consistent with mesothelioma of right pleural space associated with lung invasion.
-There is also tumor involvement on the lymphadenopathy at right mediastinum.
-The SVC is displaced anteriorly and tumor infiltration at subcarinal region and invasion to the right pericardium are also found. The mediastinum is displaced toward left side.

Diagnosis :
Mesothelioma

Discussion :
Malignant Mesothelioma =DIFFUSE MALIGNANT MESOTHELIOMA =most common primary neoplasm of pleura

Spread:
-(a)contiguous: chest wall, mediastinum, contralateral chest, pericardium, diaphragm, peritoneal cavity; lymphatics, blood
-(b)lymphatic: hilar + mediastinal (40%), celiac (8%), axillary + supraclavicular (1%), cervical nodes
-(c)hematogenous: lung, liver, kidney, adrenal gland
-extensive irregular lobulated bulky pleural-based masses typically >5 cm / pleural thickening (60%)
-exudative / hemorrhagic unilateral pleural effusion (30-60-80%) without mediastinal shift ("frozen hemithorax" = fixation by pleural rind of neoplastic tissue); effusion contains hyaluronic acid in 80-100%; bilateral effusions (in 10%)
-distinct pleural mass without effusion (<25%)
-associated with pleural plaques in 50% = pathologic HALLMARK of asbestos exposure
-pleural calcifications (20%)
-circumferential encasement = involvement of all pleural surfaces (mediastinum, pericardium, fissures) as late manifestation
-extension into interlobar fissures (40-86%) rib destruction in 20% (in advanced disease)
-ascites (peritoneum involved in 35%)

CT:
-pleural thickening (92%)
-thickening of interlobar fissure (86%)
-pleural effusion (74%)
-contraction of affected hemithorax (42%):
--ipsilateral mediastinal shift
--narrowed intercostal spaces
--elevation of ipsilateral hemidiaphragm
-calcified pleural plaques (20%)

MR (best modality to determine resectability):  
-minimally hyperintense relative to muscle on T1WI
-moderately hyperintense relative to muscle on T2WI

DDx:
pleural fibrosis from infection (TB, fungal, actinomycosis), fibrothorax, empyema, metastatic adenocarcinoma (differentiation impossible)