This study adopted a bidirectional cohort study design. On the one hand, the previous clinical data, treatment exposure and clinical endpoint events of the enrolled patients were retrospectively collected. On the other hand, prospective regular follow-up was conducted from the date of enrollment to continuously observe long-term recurrence, progression and survival outcomes, and analyze the correlation between related factors and prognosis. The primary objective of this study was to describe the efficacy and safety of SIRT-Y90 in combination with atezolizumab and bevacizumab in adult patients with unresectable HCC in China. Medical records from approximately eight sites in China will be used.

Inclusion criteria:

Age ≥18 years old A diagnosis of unresectable HCC was made. HCC can be diagnosed clinically or pathologically.

At least one Atezo plus Bev administration and one cycle of SIRT-Y90 treatment. At least one visit was recorded after the initiation of Atezo + Bev and SIRT-Y90

Exclusion criteria:

Concomitant cancers other than BCC were diagnosed before or at the start of Atezo + Bev or SIRT-Y90 Participate in an interventional clinical study before or at the time of initiation of treatment with Atezo + Bev or SIRT-Y90 Primary endpoint Objective response rate: defined as the percentage of patients who had a complete response (CR) or partial response (PR) at the follow-up date. If multiple response assessments were available within that time frame, the best overall response (BOR) was applied. Both RECIST 1.1 and mRECIST will be used to assess tumor response Solution. Secondary Endpoints Progression-Free Survival(PFS): Defined as the time from the index date to disease progression or death from any cause, whichever occurs first. Patients with unknown progression or death will be right-censored at the end of follow-up.

Overall Survival(OS): Defined as the time from the index date to death from any cause. Patients with unknown death will be right-censored at the end of follow-up.

Serum Alpha-Fetoprotein (AFP) Reduction: Serum AFP reduction is defined as a >50% decrease in AFP levels compared to baseline serum AFP levels, measured 3 months (±4 weeks) after initiation of Atezo + Bev or SIRT-Y90 treatment, whichever occurs later. The serum AFP level closest to the target time point will be used.

Adverse Events: Secondary variables/outcomes related to safety will be assessed based on actual medical records. Any adverse events (AEs) extracted from the medical records will be collected. Particular attention will be given to radiation-related AEs and immune-related AEs (irAEs).

Inclusion Criteria:

• Age ≥18 years old A diagnosis of unresectable HCC was made. HCC can be diagnosed clinically or pathologically.

At least one Atezo plus Bev administration and one cycle of SIRT-Y90 treatment. At least one visit was recorded after the initiation of Atezo + Bev and SIRT-Y90

Exclusion Criteria:

• Concomitant cancers other than BCC were diagnosed before or at the start of Atezo + Bev or SIRT-Y90 Participate in an interventional clinical study before or at the time of initiation of treatment with Atezo + Bev or SIRT-Y90

Unresectable HCC patients receiving SIRT-Y90 combined with atezolizumab and bevacizumab (including some patients who received only SIRT-Y90 treatment)

Undecided