肝細胞癌の再照射

Re-irradiation for hepatocellular carcinoma

肝細胞癌（hepatocellular carcinoma：HCC）は罹患率・死亡率ともに高く，治療後の再発率が高いことが大きな臨床課題である^1）。再発の多くは肝内に生じ，肝機能低下や既治療の影響により外科切除や局所療法の適応が制限される場合が多い^2）。

Hepatocellular carcinoma（HCC）shows high recurrence, often intrahepatic, limiting repeat surgery or local therapies due to impaired liver function. Advances in radiotherapy, including IMRT, SBRT, and particle therapy, have improved safety and efficacy, increasing interest in re-irradiation. Although evidence remains limited, studies report high local control and potential long-term survival with appropriate selection. Outcomes vary by liver function and tumor factors. Re-irradiation requires careful dose evaluation and planning due to cumulative dose and anatomical changes. Toxicities, especially liver damage, are generally acceptable with modern techniques. Further prospective studies are needed to establish optimal indications and protocols.