Primary malignant mesothelioma of the diaphragm with liver invasion: A case report and review of literature

RATIONALE: Malignant mesothelioma is a malignant tumor with poor prognosis, which usually originates in the pleura, peritoneum, and pericardial cavity. Mesotheliomas that originate from the diaphragm are very rare. Here, we report a case of primary malignant mesothelioma of the diaphragm with liver invasion. PATIENT CONCERNS: A 66-year-old woman was admitted to our hospital because of a “liver space-occupying lesion,” without any special clinical symptoms. Imaging examinations suggested a cystic-solid mixed lesion in the right lobe of the liver. DIAGNOSIS: The tumor was diagnosed as epithelioid mesothelioma of the diaphragm with liver invasion. INTERVENTION: The patient underwent abdominal surgery in our hospital to remove the diaphragmatic mass, liver mass, and part of the diaphragm. OUTCOMES: The postoperative course was uneventful. LESSONS: Primary diaphragmatic malignant mesothelioma is very rare and may involve liver or lung tissue and be mistaken for liver or lung tumor. Accurate diagnosis depends on careful pathological examination. Immunohistochemical staining is very useful to distinguish this tumor from other liver or diaphragmatic tumors.