Liver die.

Normal tissue constraints may need a refresher in the era of ultra-hypofractionated everything. This dosimetric analysis of 108 patients treated for hepatocellular carcinoma (HCC) in 15 fractions or less, roughly half and half treated with photons and protons, looked for dosimetric predictions of two clinical endpoints three months out from treatment: a 2+ increase in Child-Pugh (CP) score or a 1+ increase in Albumin-Bilirubin (ALBI) grade. Unlike previous recommendations to mind liver mean dose, this study indicates the volume of normal liver receiving very low doses is most predictive of the above outcomes. Importantly, this effect was continuous with dose with no clear “critical volume” component, though they do recommend a V5 Gy < 60%. TBL: The volume of healthy liver receiving very low doses during hypofractionated radiation deserves review during treatment planning. | Pursley, Int J Radiat Oncol Biol Phys 2020