Radiation Segmentectomy for Hepatocellular Carcinoma: Redefining the Limits of Curative-Intent Therapy

Radiation segmentectomy (RS) utilizing Yttrium-90 (Y90) microspheres has emerged as a highly effective, minimally invasive locoregional therapy for hepatocellular carcinoma (HCC), particularly in early-stage disease. This precision treatment delivers ablative radiation doses directly to the tumor and its immediate surrounding parenchyma, thereby minimizing systemic toxicity and preserving healthy liver tissue. RS consistently demonstrates high objective and complete response rates, which often correlate directly with complete pathological necrosis (CPN) of the tumor, as rigorously assessed by modified Response Evaluation Criteria in Solid Tumors (mRECIST) and European Association for the Study of the Liver (EASL) criteria. This robust imaging response translates into durable local tumor control and prolonged time to disease progression. The safety and feasibility of RS are generally well-established. The procedure is typically well-tolerated, with common adverse events usually being mild and transient. Severe complications are rare, emphameasuring the procedure's precision and minimal invasiveness. Optimal outcomes are contingent upon meticulous patient selection, strict adherence to technical guidelines, and precise dosimetry. Beyond its role as a definitive therapy, RS plays a critical function in bridging and downstaging patients awaiting liver transplantation. By effectively controlling tumor burden, it enhances patient eligibility for transplantation and improves outcomes on transplant waiting lists. Furthermore, RS offers distinct advantages over other conventional locoregional therapies in specific clinical scenarios, solidifying its integral position within the comprehensive management paradigm for HCC.