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.

Objective:To analyze and summarize the clinical efficacy and safety of lymphocyte apheresis combined with plasma exchange in the treatment of patients with hepatitis B virus-related liver failure at the ascending stage.Methods:A observational study was conducted. A total of 69 hepatitis B virus-related liver failure at the ascending stage patients who were hospitalized at Affiliated Guangzhou Eighth People's Hospital of Guangzhou Medical University from January 2016 to December 2020 were enrolled in this study. The patients were grouped according to their condition and wishes, including 38 patients treated with conservative medical treatment (control group) and 31 patients treated with lymphocyte apheresis combined with plasma exchange based on comprehensive medical treatment (study group). Clinical data were compared between the two groups 1-4 weeks after treatment, including dynamic changes of total bilirubin (TBil), international normalized ratio (INR), alanine aminotransferase (ALT), model for end-stage liver disease (MELD) score, and the rate of clinical improvement at 4 weeks after treatment. In addition, the adverse effects and dynamic changes of white blood cell count (WBC), lymphocyte count (LYM), platelet count (PLT), and hemoglobin (Hb) within 4 weeks after treatment were compared between the two groups.Results:Both groups showed significant improvement in clinical parameters after 1-4 weeks of initiation of therapy. The improvement of TBil, INR and MELD score at 1-4 weeks after treatment were significantly better in the treatment group than those in the control group [TBil (μmol/L): 248 (117, 335) vs. 398 (328, 464) at 1 week, 173 (116, 278) vs. 326 (184, 476) at 2 weeks, 107 (84, 235) vs. 355 (129, 467) at 3 weeks, 70 (61, 172) vs. 290 (82, 534) at 4 weeks; INR: 1.72±0.70 vs. 2.13±0.69 at 1 week, 1.67±0.61 vs. 2.28±1.35 at 2 weeks, 1.65±0.75 vs. 2.15±0.92 at 3 weeks, 1.61±0.93 vs. 2.19±1.17 at 4 weeks; MELD score: 18.35±5.32 vs. 23.38±4.56 at 1 week, 16.47±5.16 vs. 23.71±7.94 at 2 weeks, 16.30±5.75 vs. 22.64±6.99 at 3 weeks, 14.63±6.76 vs. 20.97±8.19 at 4 weeks], with significant differences (all P < 0.05). In addition, ALT levels at 1 week and 2 weeks after treatment in the study group were significantly lower than those in the control group [U/L: 128 (93, 206) vs. 240 (167, 436) at 1 week, 64 (42, 110) vs. 85 (69, 143) at 2 weeks, both P < 0.05]. The rate of clinical improvement at 4 weeks after treatment in the study group was 54.84% (17/31), which was significantly higher than that in the control group [28.95% (11/38)], with statistically significant difference ( P < 0.05). There was no significant difference in the rate of new infection between the study group and the control group [22.58% (7/31) vs. 34.21% (13/38), P > 0.05]. Additionally, expect that the PLT level at 1 week after treatment in the study group was significantly lower than that in the control group (×10 9/L: 101±42 vs. 128±59, P < 0.01), there was no significant difference in WBC, LYM or Hb at different time points after treatment between the two groups. Conclusion:Clinical efficacy of lymphocyte apheresis combined with plasma exchange based on comprehensive medical treatment in the treatment of patients with hepatitis B virus-related liver failure at the ascending stage is superior to conservative medical treatment alone, which can improve clinical improvement rate and recovery rate of liver function with high safety.