Malignant pleural mesothelioma: epithelial type
CT findings in a case of mesothelioma include: pleural effusion, nodular pleural thickening, thickening of the fissures and typically the whole lung is encased by the tumor with a rindlike appearance.
Pleural mesothelioma is a locally malignant tumor that may be complicated by the invasion of the chest wall, mediastinum, and diaphragm.
Signs of invasion of the thoracic wall may include chest wall involvement may manifest as haziness of the extrapleural fat planes, the involvement of the intercostal muscles or invasion and destruction of the rib.
Signs of invasion of vascular or mediastinal structures may include obliteration of surrounding fat planes, and encasing more than 50% of the organ's circumference.
Signs of invasion of the pericardium include nodular pericardial thickening or pericardial effusion.
Two specimens were received
1- Parietal pleura: 2 pieces of rubbery and flat grayish white tissue 8x4 cm and 4x2 cm.
2- Diaphragmatic nodules: pieces of rubbery grayish tissue 4x3x2 cm.
Examination of sections from both specimens received showed pieces of pleural tissue formed of moderately pleomorphic and cohesive neoplastic epithelioid cells having large hyperchromatic nuclei and adequate cytoplasm. They were displayed in glandular structure. The stromal background was fibrotic and infiltrated by chronic inflammatory cells.
Parietal pleural biopsy and free nodules on the diaphragmatic surface: picture is compatible with malignant mesothelioma epithelioid type.