New Staging Model for Radiation-based Hepatocellular Carcinoma Treatment: A National Multicenter Study

Background and Aims: The study aimed to create a new staging model for radiotherapy-based treatment for prog-nostic hepatocellular carcinoma (HCC) classification. Meth-ods: The training cohort comprised 658 patients receiving stereotactic body radiotherapy and external validation co-hort comprised 533 patients receiving three-dimensional conformal radiotherapy and intensity-modulated radiother-apy. We established a modified staging system as follows: stage I, solitary nodule without macrovascular invasion, or 2-3 nodules no more than 3.0 cm apart, and performance status (PS) 0-2 (Ia: ALBI-1 grade; Ib: ALBI-2 or 3 grade); stage II: 2-3 nodules with any one nodule more than 3.0-cm apart, or >= 4 nodules, and performance status 0-2 (IIa: ALBI-1 grade; IIb: ALBI-2 grade); stage III: macrovascular invasion, regional lymph node metastasis or distant metas-tasis, and performance status 0-2 (IIIa: ALBI-1 grade; IIIb: ALBI-2 grade); stage IV: performance status 3-4, or per-formance status 0-2 with ALBI-3 grade. We analyzed long-term overall survival based on different stages. Results: The staging model showed an excellent ability to discrimi-nate patients according to four stages and seven substages with notably different curves in the training and validation cohort. The median survival decreased from stages I to IV with 63.0 months in stage I (not reached in Ia, and 53.0 months in Ib), 24.0 months in stage II (28.0 months in IIa, and 22.0 months in IIb), 11.0 months in stage III (18.0 months in IIIa, and 9.0 months in IIIb), and less than 9.0 months in stage IV in the training cohort. Conclusions: The modified staging model may provide an alternative for clini- cal radiation oncologists.