Pulmonary tumor thrombotic microangiopathy of hepatocellular carcinoma: A case report and review of literature

BACKGROUND: Pulmonary tumor thrombotic microangiopathy (PTTM) is a rare condition in patients with hepatocellular carcinoma (HCC); to date, few cases have been reported. While hepatic dysfunction has been focused on the later stages of HCC, the management of symptoms in PTTM is important for supportive care of the cases. For the better understanding of PTTM in HCC, the information of our recent case and reported cases have been summarized. CASE SUMMARY: A patient with HCC exhibited acute and severe respiratory failure. Radiography and computed tomography of the chest revealed the multiple metastatic tumors and a frosted glass–like shadow with no evidence of infectious pneumonia. We diagnosed his condition as acute respiratory distress syndrome caused by the lung metastases and involvement of the pulmonary vessels by tumor thrombus. Administration of prednisolone to alleviate the diffuse alveolar damages including edematous changes of alveolar wall caused by the tumor cell infiltration and ischemia showed mild improvement in his symptoms and imaging findings. An autopsy showed the typical pattern of PTTM in the lung with multiple metastases. CONCLUSION: PTTM is caused by tumor thrombi in the arteries and thickening of the pulmonary arterial endothelium leading to the symptoms of dyspnea in terminal staged patients. Therefore, supportive management of symptoms is necessary in the cases with PTTM and hence we believe that the information presented here is of great significance for the diagnosis and management of symptoms of PTTM with HCC.