OC.03.3 COMPARATIVE ANALYSIS OF ATEZOBEV’S THERAPEUTIC EFFICACY IN ADVANCED HEPATOCELLULAR CARCINOMA AMONG NON-CIRRHOTIC PATIENTS: FINDINGS FROM A RETROSPECTIVE MULTICENTER STUDY

cellular carcinoma (HCC) typically involves atezolizumab plus bevacizumab (AtezoBev) or Tyrosine Kinase Inhibitors (TKIs), regardless of the degree of liver fibrosis. However, there is limited current information regarding HCC and its treatment in patients with non-cirrhotic livers. Material and Methods: Between 2020 and 2023, 57 patients diagnosed with unresectable HCC and eligible for AtezoBev treatment were enrolled across three Italian and one French centers. These patients underwent propensity score matching in a 1:1.5 ratio with 81 patients receiving TKI treatment (15 on Lenvatinib and 66 on Sorafenib) from the retrospective ITA.LI.CA cohort. Survival analysis evaluated median overall survival (mOS), progression-free survival (PFS), and time-to-progression (TTP), while radiological response (overall response rate or ORR and disease control rate or DCR) was assessed using RECIST v1.1 or mRECIST criteria. Patients were further stratified based on liver disease etiology and age. Treatment-related adverse events (trAEs), graded according to CTCAE v5.0, were collected to assess AtezoBev safety. Additionally, predictors of mortality and tumor progression were identified using Cox regression analysis. Results: AtezoBev demonstrated superior median overall survival (mOS) compared to TKIs (18.70 vs 11.13 months, p = 0.0085), along with improved progression-free survival (PFS) (8.07 vs 5.10 months, p = 0.0032) and overall response rate (ORR) (22.8% vs 7.4%, p = 0.0095). Although time-to-progression (TTP) (9.30 vs 7.77 months, p = 0.24) and disease control rate (DCR) (47.4% vs 46.9%, p = 0.957) did not statistically differ between the treatments, the trend favored AtezoBev, with the lack of significance attributed to the relatively small sample size. These findings were consistent across age and etiology subgroups of liver disease. The incidence of treatment-related adverse events remained consistent across these subgroups. Main predictors of mortality were tumor progression and performance status, while HBV infection, AFP > 400 ng/mL, and occurrence of ascites during treatment were identified as the primary predictors of progression. Conclusions: AtezoBev demonstrated efficacy and safety among non-cirrhotic patients with advanced HCC. Its use showed superior mOS, PFS, and ORR compared to TKIs, with good tolerability. Tumor progression emerged as the key predictor of mortality, while AFP > 400 ng/mL at baseline was highlighted as a risk marker for tumor progression.