Résumé
Objective To investigate the imaging features of perivascular epithelioid cell tumor of liver (PEComa),and to improve the diagnostic level of the disease. Methods A retrospective analysis of imaging manifestations was performed on 11 cases of hepatic hemangioma confirmed by surgery and pathology. All patients underwent CT and MRI examination before PET/CT examination ,then received operation. Results Eleven cases were solitary hepatic lesions ,10 of which were located in the right lobe of the liver ,and 1 in the left. The lesions were round or quasi-circular and the diameter ranged from about 13.5cm to about 1.8 cm,with an average of 5.7 cm. CT plain scanning showed that the liver was slightly lower density ,with clear boundary. The smaller lesions were homogeneous density,while the larger ones were not,and the lower density area was visible. Enhancement of peripheral lesions in the arterial phase was enhanced. The lesions in the portal vein were not uniformly enhanced , and visible separation was found in large lesions. In the delay phase ,the lesions were significantly decreased or slightly lower. MRI plain scan showed the lesion T1WI showed moderate signal or slightly low signal ,and large lesion signal was not uniform,and T2WI lesions showed slightly high signal while DWI lesions high signal and the enhanced features were similar to those of CT. PET/CT examination showed that visible radioactive uptake of abnormal concentration or uneven concentration were found in lesions with diameter larger than 3.0 cm,and the maximum SUV value ranged from 12.2 to 3.6,with an average value of 5.7. Lesions with diameter less than 3.0 cm showed a slight concentration of radioactive uptake and the highest SUV value was 4.7,with an average value of 2.9. The only 11.8 cm lesion showed no significant radioactivity ,which was as the same as that of normal liver tissue. Delayed PET/CT imaging(1 hour)showed that SUV values of all lesions were decreased in varying degrees. Conclusion PET/CT imaging of perivascular epithelioid cell tumor of liver has its characteristics. The combina-tion of PET/CT imaging and routine imaging examination will benefit the improvement of diagnosis level obviously.