Real-world data on the effectiveness and toxicity of atezolizumab and bevacizumab as first-line therapy in patients with unresectable or metastatic hepatocellular carcinoma in Costa Rica.

Abstract

e16189 Background: Hepatocellular carcinoma (HCC) remains a leading cause of cancer-related mortality globally. The combination of atezolizumab and bevacizumab has been established as a standard first-line treatment for unresectable or metastatic HCC. However, real-world data, particularly from Central America, remain scarce. This study provides the first real-world analysis from Costa Rica, evaluating the effectiveness and safety of this combination therapy in patients with advanced HCC. Methods: This retrospective, observational, multicenter study analyzed 52 patients diagnosed with unresectable or metastatic HCC treated between 2020 and 2022 at five major Costa Rican hospitals: Hospital México, Max Peralta, San Juan de Dios, Calderón Guardia, and San Vicente de Paul. Patients received atezolizumab and bevacizumab as first-line therapy. Progression-free survival (PFS), overall survival (OS), response rates, and adverse events (AEs) were evaluated. PFS and OS were estimated using Kaplan-Meier analysis, and treatment-related toxicity was graded according to the Common Terminology Criteria for Adverse Events (CTCAE v5.0). Results: 52 patients were included with a median age of 65 years; 71% were male. Most patients (78%) were classified as BCLC stage C. Chronic hepatitis B (57%) and hepatitis C (21%) were the most common etiologies, followed by non-alcoholic steatohepatitis (NASH) (39%). The median PFS was 10.0 months (95% CI: 6.0–12.0), while the median OS reached 25.5 months (95% CI: 18.7–37.2). At 12 months, the OS probability was 79%, declining to 34% at 36 months. Men demonstrated a longer PFS (11.0 months) compared to women (6.5 months), though this difference was not statistically significant (p = 0.70). The objective response rate (ORR) was 48%, with a disease control rate (DCR) of 73%. Adverse events occurred in 90% of patients, with hypertension and proteinuria being the most common (22%), primarily of grade 1–2. Serious toxicities (grade 3–5), including upper gastrointestinal bleeding, were reported in 3.77% of patients. Dose modifications were necessary in 16% of cases but did not negatively affect survival outcomes. Conclusions: This real-world study highlights the effectiveness and safety of atezolizumab and bevacizumab as first-line therapy for unresectable or metastatic HCC in Costa Rica. Outcomes in terms of PFS, OS, and toxicity are consistent with global pivotal trials, validating the regimen's use in this population. As the first real-world evaluation in Central America, these findings underscore the critical need for regional data to optimize treatment strategies and better address the unique patient profiles and disease etiologies in the region.