due to their physical advantages that deposit maximum energy sharply, with a penetration range. The
advantage of particle beam RT enables the delivery of an
adequate dose to the tumor while minimizing the dose
to surrounding normal tissue [11]. Proton therapy and
C-ion RT for HCC were reported to be effective and well
tolerated for advanced tumors [12–14]. In addition, carbon
ion beams have a higher relative biological effect
due to larger mean linear energy transfer [15]. However,
no previous reports have compared dose volume parameters
for C-ion RT versus SBRT with regard to target
volume coverage and sparing of organ at risk. Therefore,
the purpose of this study was to compare the dose
volume parameters to the target and organ at risk using
C-ion RT and SBRT in patients with HCC.