Liver abscess is a rare but serious complication of hepatocellular carcinoma after TACE, with an incidence of less than 1% reported in previous literature. Studies have shown that history of biliary tract disease, tumor size, embolization materials and embolization endpoint selection may be related to the occurrence of abscess. In recent years, with the wide application of targeted and immune drugs, there have been reports of multiple cases of liver abscess after single target immunotherapy for liver cancer, and there have also been studies showing that TACE combined with targeted immunotherapy can significantly increase the degree of liquefaction necrosis and increase the risk of liver abscess. However, these studies are single-center reports with small sample size and low level of evidence. Therefore, it is of great clinical significance to explore the risk factors of liver abscess after TACE and build a prediction model by using multi-center and large sample data. The formation of liver abscess after TACE means a large range of tissue liquefaction necrosis. There are reports of high incidence of early recurrence and metastasis of liquefaction necrosis. Some studies also show that tumor necrosis is more complete when liver abscess is combined with complete remission. In previous studies, ORR in patients with liver cancer complicated with liver abscess ranged from 18.75%-100%, with significant differences in reports from different centers. The effect of specific abscess formation on TACE efficacy of liver cancer remains to be determined. Therefore, the second research focus of this project is to explore the effect of liver abscess formation after TACE on prognosis of liver cancer.

Inclusion Criteria:

1. Case group inclusion criteria:

   1. Time period of inclusion: 2009-2023 (15 years)
   2. Patients with HCC diagnosed by clinical or pathological criteria according to the National Health Commission guidelines for the diagnosis and treatment of primary liver cancer who underwent TACE after surgery and developed postoperative liver abscess.
   3. Appendix: Diagnostic criteria for liver abscess after TACE:

   Condition 1: CT images show typically low-density lesions with or without air and fluid levels

   Condition 2:

   • positive blood culture
   • Percutaneous drainage or aspiration is purulent or culture-positive
   • Symptoms of infection such as fever/chills, accompanied by elevated inflammatory markers such as white blood cell count, C-reactive protein, or procalcitonin.

2. Control group inclusion criteria

   1. Patients with HCC without liver abscess who underwent TACE in the same center within the week of treatment in the case group.

      -

      Exclusion Criteria:

   1. Clinical and follow-up data were incomplete
   2. Loss to follow-up

HCC patients from hospital interventional wards receiving TACE