Open AccessDelayed response to proton beam treatment of hepatocellular carcinoma
Author(s) -
Chee-Wai Cheng,
Mitchell Machtay,
Jennifer A. Dorth,
Olga Sergeeva,
Hangsheng Xia,
Chawan Manaspon,
Han-Ping Wu,
Renuka Iyer,
Sandra Sexton,
Xin Wei,
Agata A. Exner,
Zhenghong Lee
Publication year - 2020
Publication title -
bjr case reports
Language(s) - English
Resource type - Journals
ISSN - 2055-7159
DOI - 10.1259/bjrcr.20180125
Subject(s) - medicine , hepatocellular carcinoma , radiology , nuclear medicine , radiation treatment planning , nodule (geology) , ultrasound , radiation therapy , paleontology , biology
Hepatocellular carcinoma (HCC) has become one of the leading causes of cancer death worldwide. There has been anecdotal report regarding the effectiveness of proton beam treatment for HCC. In this pre-clinical investigation, the woodchuck model of viral hepatitis infection-induced HCC was used for proton beam treatment experiment. The radiopaque fiducial markers that are biodegradable were injected around the tumor under ultrasound guidance to facilitate positioning in sequential treatments. An α cradle mode was used to ensure reproducibility of animal positioning on the treatment couch. A CT scan was performed first for contouring by a radiation oncologist. The CT data set with contours was then exported for dose planning. Three fractionations, each 750 CcGyE, were applied every other day with a Mevion S250 passive scattering proton therapy system. Multiphase contrast-enhanced CT scans were performed after the treatment and at later times for follow-ups. 3 weeks post-treatment, shrinking of the HCC nodule was detected and constituted to a partial response (30% reduction along the long axis). By week nine after treatment, the nodule disappeared during the arterial phase of multiphase contrast-enhanced CT scan. Pathological evaluation corroborated with this imaging response. A delayed, but complete imaging response to proton beam treatment applied to HCC was achieved with this unique and clinically relevant animal model of HCC.