Hong, TheodoreDelaney, ThomasMamon, HarveyWillett, Christopher G.Yeap, BeowNiemierko, AndrzejWolfgang, JohnLu, Hsiao-MingAdams, JudithWeyman, Elizabeth A.Arellano, RonaldBlaszkowsky, LawrenceAllen, JillTanabe, KennethRyan, DavidZhu, Andrew2017-04-252014Hong, Theodore S., Thomas F. DeLaney, Harvey J. Mamon, Christopher G. Willett, Beow Y. Yeap, Andrzej Niemierko, John A. Wolfgang, et al. 2014. “A Prospective Feasibility Study of Respiratory-Gated Proton Beam Therapy for Liver Tumors.” Practical Radiation Oncology 4 (5) (September): 316–322. doi:10.1016/j.prro.2013.10.002.1879-8500http://nrs.harvard.edu/urn-3:HUL.InstRepos:32434447Purpose To evaluate the feasibility of a respiratory-gated proton beam therapy for liver tumors. Materials and Methods Fifteen patients were enrolled on a prospective IRB-approved protocol. Eligibility criteria included Childs-Pugh A/B cirrhosis, unresectablebiopsy-proven hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (ICC), or metastatic disease (solid tumors only), 1-3 lesions, and tumor size of ≤6 cm. Patients received 15 fractions to a total dose of 45-75 GyE using respiratory-gated proton beam therapy. Gating was performed with an external respiratory position monitoring (RPM) based system. Results Of the15 patients enrolled on this clinical trial, 11 had HCC, 3 had ICC, and 1had metastasis from another primary. Ten patients had a single lesion, 3 patients had 2 lesions, and 2 patients 3 lesions. Toxicities were: Gr 3 bilirubinemia- 2, Gr 3 gastrointestinal bleed- 1, and Gr 5 stomach perforation-1. One patient had a marginal recurrence, 3 had hepatic recurrences elsewhere in the liver, and 2 had extrahepatic recurrence. With a median follow-up for survivors of 69 months, 1-yr, 2-yr, 3-yr OS is 53%, 40%, and 33% respectively. PFS is 40%,33% and 27% at 1, 2, and 3 years, respectively. Conclusion Respiratory-gated proton beam therapy for liver tumors is feasible. Phase II studies for primary liver tumors and metastatic tumorsare underway.en-USJournal Article2017-03-2220142017-04-2510.1016/j.prro.2013.10.002