Respiratory-gated Proton Beam Therapy for Hepatocellular Carcinoma Adjacent to the Gastrointestinal Tract without Fiducial Markers.

Miu Mizuhata,Hiroyasu Tamamura,Satoshi Kobayashi,Kazutaka Yamamoto,Tomoyasu Kumano,Yoshikazu Maeda,Sayuri Bou,Yuji Tameshige,Shigeyuki Takamatsu,Satoko Asahi,Yoshitaka Sato,Makoto Sasaki,Toshifumi Gabata,Satoshi Shibata,Mariko Kawamura

doi:10.3390/cancers10020058

Abstract

The efficacy of proton beam therapy (PBT) for hepatocellular carcinoma (HCC) has been reported, but insertion of fiducial markers in the liver is usually required. We evaluated the efficacy and toxicity of respiratory-gated PBT without fiducial markers for HCC located within 2 cm of the gastrointestinal tract. From March 2011 to December 2015 at our institution, 40 patients were evaluated (median age, 72 years; range, 38–87 years). All patients underwent PBT at a dose of 60 to 80 cobalt gray equivalents (CGE) in 20 to 38 fractions. The median follow-up period was 19.9 months (range, 1.2–72.3 months). The median tumor size was 36.5 mm (range, 11–124 mm). Kaplan–Meier estimates of the 2-year overall survival, progression-free survival, and local tumor control rates were 76%, 60%, and 94%, respectively. One patient (2.5%) developed a grade 3 gastric ulcer and one (2.5%) developed grade 3 ascites retention; none of the remaining patients developed grade >3 toxicities (National Cancer Institute Common Terminology Criteria for Adverse Events ver. 4.0.). This study indicates that PBT without fiducial markers achieves good local control without severe treatment-related toxicity of the gastrointestinal tract for HCC located within 2 cm of the gastrointestinal tract.

Highlights

Hepatocellular carcinoma (HCC) is one of the most important cancers worldwide because of its generally poor prognosis [1,2]
Of the 40 patients included in this study, 38 completed proton beam therapy (PBT) according to the treatment protocol (Table 1)
One of the two who did not complete the protocol had gastric hemorrhage with an ulcer treated by transfusion, and PBT was finished earlier than the planned protocol (70 cobalt gray equivalents (CGE) in 35 Fr)

Summary

Introduction

Hepatocellular carcinoma (HCC) is one of the most important cancers worldwide because of its generally poor prognosis [1,2]. Because the liver is a radiosensitive organ, it is difficult to achieve a sufficient irradiation dose to treat HCC [5,6]. Proton beam therapy (PBT) for HCC has recently been reported to achieve good local control and less toxicity [7,8,9]. HCC adjacent to the GI tract should be carefully treated using the high-precision irradiation technique. For high-accuracy irradiation, Tsukuba University developed a respiratory gating system with fiducial markers and reported good treatment outcomes [8,11]. A four-dimensional computed tomography (4D-CT) technique was recently used to analyze the respiratory motion of the target and was shown to be useful for high-accuracy radiotherapy [12,13]

Methods

Results

Conclusion