Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Jan 1;62(1):133-141.
doi: 10.1093/jrr/rraa098.

Capacity of proton beams in preserving normal liver tissue during proton beam therapy for hepatocellular carcinoma

Yu-Lun Tsai  1 , Hideyuki Takei  2 , Takashi Iizumi  2   3 , Toshiyuki Okumura  2   3 , Yuta Sekino  2   3 , Haruko Numajiri  2   3 , Hitoshi Ishikawa  2   3 , Takeji Sakae  2 , Hideyuki Sakurai  2   3
Affiliations

Capacity of proton beams in preserving normal liver tissue during proton beam therapy for hepatocellular carcinoma

Yu-Lun Tsai et al. J Radiat Res. .

Abstract

Unirradiated liver volume (ULV) preservation rate is an important factor associated with radiation-induced liver disease (RILD) in patients with hepatocellular carcinoma (HCC) undergoing proton beam therapy (PBT). The purpose of this study is to identify the predictors for ULV preservation and quantify the capacity of proton beams in normal liver sparing during PBT. We reviewed planning data of 92 patients with single intrahepatic HCC tumors undergoing PBT. The potential clinical and planning factors that may affect ULV preservation were involved in multiple linear regression for ULV preservation rate. The significant factors were determined to be predictors and their influences were quantified. The median ULV preservation rate was 62.08%. All the assessed clinical factors showed significant effects on ULV preservation rate: clinical target volume (CTV), P < 0.001; portal vein tumor thrombosis (PVTT), P = 0.010; left lobe tumor, P = 0.010. In contrast, none of the planning factors demonstrated significance. The coefficients of significant factors in multiple linear regression were 60.85 for intercept, -0.02 for CTV, -9.01 for PVTT and 8.31 for left lobe tumors. The capacity of proton beams to spare normal liver tissue during PBT for HCC is mainly affected by clinical factors. The baseline of the ULV preservation rate is 60.85%, decreasing 0.02% with each milliliter of CTV increase and 9.01% for tumors with PVTT, and increasing 8.31% for tumors limited to the left lobe. Further clinical studies should be carried out to correlate our dosimetric findings with clinical outcomes.

Keywords: hepatocellular carcinoma; normal liver sparing; proton beam therapy; unirradiated liver volume.

PubMed Disclaimer

Figures

Fig. 1.
Fig. 1.
ULV preservation rate is defined as the ratio of ULV (red line) receiving a total dose <0.1 Gy(RBE) during PBT, to NLV, which is the whole liver volume minus CTV (white line).
Fig. 2.
Fig. 2.
Tumors limited to the left lobe have higher ULV preservation rates.
Fig. 3.
Fig. 3.
The scatter diagram to demonstrate the correlation between ULV preservation rate and CTV with regression line (straight black line). The baseline of the ULV preservation rate is 60.85%, decreasing 0.02% with each milliliter of CTV increase and adjusted by the tumor location and PVTT status.
Fig. 4.
Fig. 4.
ULV tends to decrease corresponding to CTV increase.
Fig. 5.
Fig. 5.
NLV has no correlation with CTV.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Hong TS, Wo JY, Yeap BY et al. Multi-institutional phase II study of high-dose Hypofractionated proton beam therapy in patients with localized, Unresectable hepatocellular carcinoma and intrahepatic cholangiocarcinoma. J Clin Oncol 2016;34:460–8. - PMC - PubMed
    1. Bush DA, Kayali Z, Grove R et al. The safety and efficacy of high-dose proton beam radiotherapy for hepatocellular carcinoma: A phase 2 prospective trial. Cancer 2011;117:3053–9. - PubMed
    1. Hata M, Tokuuye K, Sugahara S et al. Proton beam therapy for aged patients with hepatocellular carcinoma. Int J Radiat Oncol Biol Phys 2007;69:805–12. - PubMed
    1. Apisarnthanarax S, Bowen SR, Combs SE. Proton beam therapy and carbon ion radiotherapy for hepatocellular carcinoma. Semin Radiat Oncol 2018;28:309–20. - PubMed
    1. Hsu CY, Wang CW, Cheng AL et al. Hypofractionated particle beam therapy for hepatocellular carcinoma-a brief review of clinical effectiveness. World J Gastrointest Oncol 2019;11:579–88. - PMC - PubMed