Published in the Red Journal, this single-institution retrospective study compared clinical outcomes of proton versus photon ablative radiation therapy in patients with unresectable HCC. 49 patients were treated with protons and 84 patients with photons to a total dose of 45 Gy in 15 fractions or 30 Gy in 5 to 6 fractions. Patients treated with protons had higher incidence of underlying cirrhosis, while those treated with photons had worse baseline Child-Pugh score and worse baseline ALBI score. With the median follow-up of 14 months, this study reported that proton therapy improved OS (P = .008).

The median OS for proton- and photon-treated patients was 31 and 14 months, and the 2-yar OS for proton- and photon-treated patients was 59.1% and 28.6%. There was no difference in local control at 2 years of 93% and 90% for protons and photons. 21 patients developed nonclassic RILD, including 4 proton-treated and 17 photon treated patients which proton therapy was associated with decreased risk of nonclassic RILD (P= .03). This study concluded that proton radiation therapy was associated with improved survival, which may be driven by decreased incidence of posttreatment liver decompensation.