1. Bray F, Ferlay J, Soerjomataram I, Siegel RL, Torre LA, Jemal A. Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin. 2018; 68:394–424.
2. Zhu RX, Seto WK, Lai CL, Yuen MF. Epidemiology of hepatocellular carcinoma in the Asia-Pacific region. Gut Liver. 2016; 10:332–339.
3. Choo SP, Tan WL, Goh BKP, Tai WM, Zhu AX. Comparison of hepatocellular carcinoma in Eastern versus Western populations. Cancer. 2016; 122:3430–3446.
4. Sinn DH, Choi GS, Park HC, Kim JM, Kim H, Song KD, et al. Multidisciplinary approach is associated with improved survival of hepatocellular carcinoma patients. PLoS One. 2019; 14:e0210730.
5. Keane FK, Hong TS. Role and future directions of external beam radiotherapy for primary liver cancer. Cancer Control. 2017; 24:1073274817729242.
6. Park HC, Yu JI, Cheng JC, Zeng ZC, Hong JH, Wang ML, et al. Consensus for radiotherapy in hepatocellular carcinoma from The 5th Asia-Pacific Primary Liver Cancer Expert Meeting (APPLE 2014): current practice and future clinical trials. Liver Cancer. 2016; 5:162–174.
7. Bang A, Dawson LA. Radiotherapy for HCC: ready for prime time? JHEP Rep. 2019; 1:131–137.
8. Dawson LA. Overview: Where does radiation therapy fit in the spectrum of liver cancer local-regional therapies? Semin Radiat Oncol. 2011; 21:241–246.
9. Yu Y, Feng M. Radiotherapy for hepatocellular carcinoma. Semin Radiat Oncol. 2018; 28:277–287.
10. European Association for the Study of the Liver. European Association for the Study of the Liver. EASL clinical practice guidelines: management of hepatocellular carcinoma. J Hepatol. 2018; 69:182–236.
11. Marrero JA, Kulik LM, Sirlin CB, Zhu AX, Finn RS, Abecassis MM, et al. Diagnosis, staging, and management of hepatocellular carcinoma: 2018 practice guidance by the American Association for the Study of Liver Diseases. Hepatology. 2018; 68:723–750.
12. Omata M, Cheng AL, Kokudo N, Kudo M, Lee JM, Jia J, et al. Asia-Pacific clinical practice guidelines on the management of hepatocellular carcinoma: a 2017 update. Hepatol Int. 2017; 11:317–370.
13. Chiba T, Tokuuye K, Matsuzaki Y, Sugahara S, Chuganji Y, Kagei K, et al. Proton beam therapy for hepatocellular carcinoma: a retrospective review of 162 patients. Clin Cancer Res. 2005; 11:3799–3805.
14. Sugahara S, Oshiro Y, Nakayama H, Fukuda K, Mizumoto M, Abei M, et al. Proton beam therapy for large hepatocellular carcinoma. Int J Radiat Oncol Biol Phys. 2010; 76:460–466.
15. Takeda A, Sanuki N, Tsurugai Y, Iwabuchi S, Matsunaga K, Ebinuma H, et al. Phase 2 study of stereotactic body radiotherapy and optional transarterial chemoembolization for solitary hepatocellular carcinoma not amenable to resection and radiofrequency ablation. Cancer. 2016; 122:2041–2049.
16. Yoon SM, Lim YS, Park MJ, Kim SY, Cho B, Shim JH, et al. Stereotactic body radiation therapy as an alternative treatment for small hepatocellular carcinoma. PLoS One. 2013; 8:e79854.
17. Korean Liver Cancer Association, National Cancer Center. 2018 Korean Liver Cancer Association-National Cancer Center Korea Practice Guidelines for the management of hepatocellular carcinoma. Gut Liver. 2019; 13:227–299.
18. Kim TH, Kim DY, Park JW, Kim SH, Choi JI, Kim HB, et al. Dose-volumetric parameters predicting radiation-induced hepatic toxicity in unresectable hepatocellular carcinoma patients treated with three-dimensional conformal radiotherapy. Int J Radiat Oncol Biol Phys. 2007; 67:225–231.
19. Hong TS, Wo JY, Yeap BY, Ben-Josef E, McDonnell EI, Blaszkowsky LS, 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; 34:460–468.
20. Kang JK, Kim MS, Cho CK, Yang KM, Yoo HJ, Kim JH, et al. Stereotactic body radiation therapy for inoperable hepatocellular carcinoma as a local salvage treatment after incomplete transarterial chemoembolization. Cancer. 2012; 118:5424–5431.
21. Kim TH, Park JW, Kim YJ, Kim BH, Woo SM, Moon SH, et al. Phase I dose-escalation study of proton beam therapy for inoperable hepatocellular carcinoma. Cancer Res Treat. 2015; 47:34–45.
22. Wahl DR, Stenmark MH, Tao Y, Pollom EL, Caoili EM, Lawrence TS, et al. Outcomes after stereotactic body radiotherapy or radiofrequency ablation for hepatocellular carcinoma. J Clin Oncol. 2016; 34:452–459.
23. Choi C, Koom WS, Kim TH, Yoon SM, Kim JH, Lee HS, et al. A prospective phase 2 multicenter study for the efficacy of radiation therapy following incomplete transarterial chemoembolization in unresectable hepatocellular carcinoma. Int J Radiat Oncol Biol Phys. 2014; 90:1051–1060.
24. Oh D, Lim DH, Park HC, Paik SW, Koh KC, Lee JH, et al. Early three-dimensional conformal radiotherapy for patients with unresectable hepatocellular carcinoma after incomplete transcatheter arterial chemoembolization: a prospective evaluation of efficacy and toxicity. Am J Clin Oncol. 2010; 33:370–375.
25. Han KH, Seong J, Kim JK, Ahn SH, Lee DY, Chon CY. Pilot clinical trial of localized concurrent chemoradiation therapy for locally advanced hepatocellular carcinoma with portal vein thrombosis. Cancer. 2008; 113:995–1003.
26. Im JH, Yoon SM, Park HC, Kim JH, Yu JI, Kim TH, et al. Radiotherapeutic strategies for hepatocellular carcinoma with portal vein tumour thrombosis in a hepatitis B endemic area. Liver Int. 2017; 37:90–100.
27. Koo JE, Kim JH, Lim YS, Park SJ, Won HJ, Sung KB, et al. Combination of transarterial chemoembolization and three-dimensional conformal radiotherapy for hepatocellular carcinoma with inferior vena cava tumor thrombus. Int J Radiat Oncol Biol Phys. 2010; 78:180–187.
28. Yoon SM, Lim YS, Won HJ, Kim JH, Kim KM, Lee HC, et al. Radiotherapy plus transarterial chemoembolization for hepatocellular carcinoma invading the portal vein: long-term patient outcomes. Int J Radiat Oncol Biol Phys. 2012; 82:2004–2011.
29. Yu JI, Park HC, Lim DH, Park W, Yoo BC, Paik SW, et al. Prognostic index for portal vein tumor thrombosis in patients with hepatocellular carcinoma treated with radiation therapy. J Korean Med Sci. 2011; 26:1014–1022.
30. Yu JI, Park JW, Park HC, Yoon SM, Lim DH, Lee JH, et al. Clinical impact of combined transarterial chemoembolization and radiotherapy for advanced hepatocellular carcinoma with portal vein tumor thrombosis: an external validation study. Radiother Oncol. 2016; 118:408–415.
31. Yoon SM, Ryoo BY, Lee SJ, Kim JH, Shin JH, An JH, et al. Efficacy and safety of transarterial chemoembolization plus external beam radiotherapy vs sorafenib in hepatocellular carcinoma with macroscopic vascular invasion: a randomized clinical trial. JAMA Oncol. 2018; 4:661–669.
32. Kim Y, Park HC, Yoon SM, Kim TH, Lee J, Choi J, et al. Prognostic group stratification and nomogram for predicting overall survival in patients who received radiotherapy for abdominal lymph node metastasis from hepatocellular carcinoma: a multi-institutional retrospective study (KROG 15-02). Oncotarget. 2017; 8:94450–94461.
33. Yoon SM, Kim JH, Choi EK, Ahn SD, Lee SW, Yi BY, et al. Radio-response of hepatocellular carcinoma-treatment of lymph node metastasis. Cancer Res Treat. 2004; 36:79–84.
34. Zeng ZC, Tang ZY, Fan J, Qin LX, Ye SL, Zhou J, et al. Consideration of role of radiotherapy for lymph node metastases in patients with HCC: retrospective analysis for prognostic factors from 125 patients. Int J Radiat Oncol Biol Phys. 2005; 63:1067–1076.
35. Jung J, Yoon SM, Park HC, Nam TK, Seong J, Chie EK, et al. Radiotherapy for adrenal metastasis from hepatocellular carcinoma: a multi-institutional retrospective study (KROG 13-05). PLoS One. 2016; 11:e0152642.
36. Jiang W, Zeng ZC, Zhang JY, Fan J, Zeng MS, Zhou J. Palliative radiation therapy for pulmonary metastases from hepatocellular carcinoma. Clin Exp Metastasis. 2012; 29:197–205.
37. Park Y, Kim KS, Kim K, Chie EK, Kim JH, Kim JS, et al. Nomogram prediction of survival in patients with brain metastases from hepatocellular carcinoma treated with whole-brain radiotherapy: a multicenter retrospective study. J Neurooncol. 2015; 125:377–383.
38. Wang S, Wang A, Lin J, Xie Y, Wu L, Huang H, et al. Brain metastases from hepatocellular carcinoma: recent advances and future avenues. Oncotarget. 2017; 8:25814–25829.
39. He J, Zeng ZC, Tang ZY, Fan J, Zhou J, Zeng MS, et al. Clinical features and prognostic factors in patients with bone metastases from hepatocellular carcinoma receiving external beam radiotherapy. Cancer. 2009; 115:2710–2720.
40. Jung IH, Yoon SM, Kwak J, Park JH, Song SY, Lee SW, et al. High-dose radiotherapy is associated with better local control of bone metastasis from hepatocellular carcinoma. Oncotarget. 2017; 8:15182–15192.
41. Rades D, Dahlke M, Janssen S, Gebauer N, Bartscht T. Radiation therapy for metastatic spinal cord compression in patients with hepatocellular carcinoma. In Vivo. 2015; 29:749–752.
42. Seong J, Koom WS, Park HC. Radiotherapy for painful bone metastases from hepatocellular carcinoma. Liver Int. 2005; 25:261–265.
43. Kokudo N, Takemura N, Hasegawa K, Takayama T, Kubo S, Shimada M, et al. Clinical practice guidelines for hepatocellular carcinoma: The Japan Society of Hepatology 2017 (4th JSH-HCC guidelines) 2019 update. Hepatol Res. 2019; 49:1109–1113.
45. Surveillance group, Diagnosis group, Staging group, Surgery group, Local ablation group, TACE/TARE/HAI group, et al. Management consensus guideline for hepatocellular carcinoma: 2016 updated by the Taiwan Liver Cancer Association and the Gastroenterological Society of Taiwan. J Formos Med Assoc. 2018; 117:381–403.
46. Andolino DL, Johnson CS, Maluccio M, Kwo P, Tector AJ, Zook J, et al. Stereotactic body radiotherapy for primary hepatocellular carcinoma. Int J Radiat Oncol Biol Phys. 2011; 81:e447–e453.
47. Kwon JH, Bae SH, Kim JY, Choi BO, Jang HS, Jang JW, et al. Long-term effect of stereotactic body radiation therapy for primary hepatocellular carcinoma ineligible for local ablation therapy or surgical resection. Stereotactic radiotherapy for liver cancer. BMC Cancer. 2010; 10:475.
48. O’Connor JK, Trotter J, Davis GL, Dempster J, Klintmalm GB, Goldstein RM. Long-term outcomes of stereotactic body radiation therapy in the treatment of hepatocellular cancer as a bridge to transplantation. Liver Transpl. 2012; 18:949–954.
49. Cheng JC, Chuang VP, Cheng SH, Huang AT, Lin YM, Cheng TI, et al. Local radiotherapy with or without transcatheter arterial chemoembolization for patients with unresectable hepatocellular carcinoma. Int J Radiat Oncol Biol Phys. 2000; 47:435–442.
50. Meng MB, Cui YL, Lu Y, She B, Chen Y, Guan YS, et al. Transcatheter arterial chemoembolization in combination with radiotherapy for unresectable hepatocellular carcinoma: a systematic review and meta-analysis. Radiother Oncol. 2009; 92:184–194.
51. Chen SW, Lin LC, Kuo YC, Liang JA, Kuo CC, Chiou JF. Phase 2 study of combined sorafenib and radiation therapy in patients with advanced hepatocellular carcinoma. Int J Radiat Oncol Biol Phys. 2014; 88:1041–1047.
52. Huang YJ, Hsu HC, Wang CY, Wang CJ, Chen HC, Huang EY, et al. The treatment responses in cases of radiation therapy to portal vein thrombosis in advanced hepatocellular carcinoma. Int J Radiat Oncol Biol Phys. 2009; 73:1155–1163.
53. Hawkins MA, Dawson LA. Radiation therapy for hepatocellular carcinoma: from palliation to cure. Cancer. 2006; 106:1653–1663.
54. Zhou J, Sun HC, Wang Z, Cong WM, Wang JH, Zeng MS, et al. Guidelines for diagnosis and treatment of primary liver cancer in China (2017 edition). Liver Cancer. 2018; 7:235–260.
55. Wang WH, Wang Z, Wu JX, Zhang T, Rong WQ, Wang LM, et al. Survival benefit with IMRT following narrow-margin hepatectomy in patients with hepatocellular carcinoma close to major vessels. Liver Int. 2015; 35:2603–2610.
56. Zeng ZC, Fan J, Tang ZY, Zhou J, Qin LX, Wang JH, et al. A comparison of treatment combinations with and without radiotherapy for hepatocellular carcinoma with portal vein and/or inferior vena cava tumor thrombus. Int J Radiat Oncol Biol Phys. 2005; 61:432–443.
57. Poon RT, Cheung TT, Kwok PC, Lee AS, Li TW, Loke KL, et al. Hong Kong consensus recommendations on the management of hepatocellular carcinoma. Liver Cancer. 2015; 4:51–69.
58. Chan LC, Chiu SK, Chan SL. Stereotactic radiotherapy for hepatocellular carcinoma: report of a local single-centre experience. Hong Kong Med J. 2011; 17:112–118.
59. Honda Y, Kimura T, Aikata H, Kobayashi T, Fukuhara T, Masaki K, et al. Stereotactic body radiation therapy combined with transcatheter arterial chemoembolization for small hepatocellular carcinoma. J Gastroenterol Hepatol. 2013; 28:530–536.
60. Law AL, Ng WT, Lee MC, Chan AT, Fung KH, Li F, et al. Treatment of primary liver cancer using highly-conformal radiotherapy with kV-image guidance and respiratory control. Radiother Oncol. 2012; 102:56–61.
61. Tang QH, Li AJ, Yang GM, Lai EC, Zhou WP, Jiang ZH, et al. Surgical resection versus conformal radiotherapy combined with TACE for resectable hepatocellular carcinoma with portal vein tumor thrombus: a comparative study. World J Surg. 2013; 37:1362–1370.
62. Xu LT, Zhou ZH, Lin JH, Chen Z, Wang K, Wang P, et al. Clinical study of transarterial chemoembolization combined with 3-dimensional conformal radiotherapy for hepatocellular carcinoma. Eur J Surg Oncol. 2011; 37:245–251.
63. Cheung TT, Kwok PC, Chan S, Cheung CC, Lee AS, Lee V, et al. Hong Kong consensus statements for the management of unresectable hepatocellular carcinoma. Liver Cancer. 2018; 7:40–54.
64. Sapisochin G, Barry A, Doherty M, Fischer S, Goldaracena N, Rosales R, et al. Stereotactic body radiotherapy vs. TACE or RFA as a bridge to transplant in patients with hepatocellular carcinoma. An intention-to-treat analysis. J Hepatol. 2017; 67:92–99.
65. Bruix J, Sherman M. American Association for the Study of Liver Diseases. Management of hepatocellular carcinoma: an update. Hepatology. 2011; 53:1020–1022.
66. Bush DA, Smith JC, Slater JD, Volk ML, Reeves ME, Cheng J, et al. Randomized clinical trial comparing proton beam radiation therapy with transarterial chemoembolization for hepatocellular carcinoma: results of an interim analysis. Int J Radiat Oncol Biol Phys. 2016; 95:477–482.
67. Huo YR, Eslick GD. Transcatheter arterial chemoembolization plus radiotherapy compared with chemoembolization alone for hepatocellular carcinoma: a systematic review and meta-analysis. JAMA Oncol. 2015; 1:756–765.
68. Jeong Y, Shin MH, Yoon SM, Song GW, Kim KH, Ahn CS, et al. Liver transplantation after transarterial chemoembolization and radiotherapy for hepatocellular carcinoma with vascular invasion. J Gastrointest Surg. 2017; 21:275–283.
69. Vogel A, Cervantes A, Chau I, Daniele B, Llovet JM, Meyer T, et al. Hepatocellular carcinoma: ESMO clinical practice guidelines for diagnosis, treatment and follow-up. Ann Oncol. 2018; 29(Suppl 4):iv238–iv255..