Asymptomatic late-phase radiographic changes amongst chest wall patients are associated with a proton RBE exceeding 1.1

For matched proton and photon cohorts of chest-wall patients, asymptomatic late-phase radiographic changes within the lung were found to be significantly more prominent amongst those treated with protons. An en-face proton beam arrangement was used. RBE elevation could be attributable to either (i) the late, normal tissue endpoint considered, (ii) end-of-range proton LET elevation, or a combination of these two. Regardless, our results suggest that clinically-relevant proton RBEs exceed 1.1 under certain circumstances.

https://ift.tt/2H9YuG6