Advanced Hepatocellular Carcinoma Patients with Poor Access to Systemic Therapy Treated with Definitive Stereotactic Body Radiation Therapy: A Single-Institution Experience in Latin America

Abstract

The standard treatment for patients with advanced hepatocellular carcinoma (aHCC) is systemic therapy with or without stereotactic body radiation therapy (SBRT). We present our experience using SBRT as a definitive treatment for aHCC patients with poor access to systemic therapy. We performed a retrospective review of patients treated with SBRT at the largest institution in Santiago, Chile between June 2016 and September 2022. All patients were deemed unsuitable for another locoregional treatment by the tumor board. We registered demographic, clinical and treatment characteristics. Additionally, treatment response rates using mRECIST criteria, overall survival (OS), local control (LC) and treatment toxicity were reported. We performed a multivariate analysis of variables using Cox proportion hazard ratio for OS and logistic regression for LC. A total of 59 patients were included (41 males and 18 females; median age: 70 years [range: 38 - 85 years]), with a total of 63 treatment courses. Most common etiologies of chronic liver disease were nonalcoholic fatty liver disease (23%) and chronic alcohol consumption (20%). Most patients were classified as Child-Pugh Class A (80%). Barcelona Clinic Liver Cancer (BCLC) stage was 2%, 11%, 49% and 38% for stages 0, A, B and C, respectively, while macrovascular invasion was present in 10 (18%) of patients. Forty-six patients (73%) had been subjected to prior locoregional therapy and only 5 patients (8,5%) received systemic therapy after SBRT. Median tumor size was 7 cm. (range: 0.95 - 32 cm). Median radiation dose was 40 Gy (range: 26.5 - 50 Gy) in 5 fractions. Evaluation of radiological response was performed in 46 patients (79%), with complete response, partial response, stable disease and progressive disease in 41%, 43%, 7% and 9% of the cohort, respectively. With a median follow-up of 9 months (range: 0 - 58), 34 patients (58%) died with a median OS of 10.8 months (range: 0 - 28 months). At 12 months, OS was 65.2% (95% CI: 50.9 - 76.3) and at 24 months was 40.7% (95% CI: 26.2 - 54.6) In multivariate analysis tumor size (as a continuous variable) was the only significant variable for LC (OR 2.9 [CI 1.1 - 5.3; p 0.03]) and for OS (HR 3.4 [CI 1.3 - 6.7; p< 0.01]). Four patients developed grade 3 toxicity (3 thrombocytopenia and 1 duodenal ulcer) and only two treatments were suspended definitively. Despite systemic therapy is the standard treatment for aHCC, a minor proportion of patients received the standard of care. SBRT is safe, feasible and a well-tolerated treatment option for aHCC with good clinical outcomes. To our knowledge, this is the first cohort reported of patients with aHCC treated with SBRT in Latin America.