Have we reached proton beam therapy dosimetric limitations? – A novel robust, delivery-efficient and continuous spot-scanning proton arc (SPArc) therapy is to improve the dosimetric outcome in treating prostate cancer. (4th March 2018) - Ding, Xuanfeng; Li, Xiaoqiang; Qin, An; Zhou, Jun; Yan, Di; Stevens, Craig; Krauss, Daniel; Kabolizadeh, Peyman