Local radiotherapy with or without transcatheter arterial chemoembolization for patients with unresectable hepatocellular carcinoma

Clinical efficacy and safety of external radiotherapy combined with sorafenib in the treatment of hepatocellular carcinoma: a systematic review and meta-analysis

INTRODUCTION AND OBJECTIVES

Both external radiotherapy and sorafenib are promising treatments for hepatocellular carcinoma (HCC). Nevertheless, the combined treatment of external radiotherapy and sorafenib has not been widely applied clinically due to potentially adverse effects. This meta-analysis aimed to evaluate the clinical efficacy and safety of external radiotherapy combined with sorafenib in the treatment of HCC.

METHODS

Pubmed, MEDLINE, EMBASE, Cochrane Library, and Web of Science databases were searched. The primary and secondary observation endpoints were the end of survival and incidence of adverse events, respectively. 11 studies involving 664 patients were included in this meta-analysis.

RESULTS

The results demonstrated that median overall survival (mOS) and median progression-free survival (mPFS) of the external radiotherapy combined with sorafenib (RS) group were 19.45 months and 8.20 months. The one- and two-year survival rates were 0.65 (95%CI: 0.55-0.76) and 0.40 (95%CI: 0.24-0.56). The incidence of adverse events was 0.34 (95%CI: 0.25-0.44).

CONCLUSIONS

The findings demonstrated that the survival of the RS group was significantly improved and few severe adverse events were observed. Hence, it can be concluded that external radiotherapy combined with sorafenib is a safe, effective, and promising therapeutic option for HCC.

Association between chemotherapy and prognostic factors of survival in hepatocellular carcinoma: a SEER population-based cohort study

Hepatectomy and transplantation are the main surgical therapies for HCC patients, and radiotherapy or chemotherapy is often used as adjuvant treatment. Researches have evaluated the independent predictors of HCC, but evidence for factors predicting the efficacy of chemotherapy is rare. Patients diagnosed with HCC between 2010 and 2015 from the SEER database were included and randomly divided into non-chemotherapy and chemotherapy groups. The predictors of CSS and OS were analyzed with the Cox proportional-hazards regression model and Fine and Gray’s competing risk model. Although there was no significant difference in survival analysis between the chemotherapy and non-chemotherapy groups, the cumulative cancer-specific mortality of most HCC patients was decreased in the chemotherapy group. AJCC stage, tumor size, grade, surgery and radiotherapy were predictors of OS and CSS in the non-chemotherapy group, while AJCC stage, tumor size, AFP, grade and surgery in the chemotherapy group. Surgery combined with chemotherapy was applicable to all AJCC stage patients. Surgery was the major treatment option for patients in AJCC I and AJCC II stage, and chemotherapy in AJCC III and AJCC IV stage. In conclusion, the study provided population-based estimates of the prognostic factors in HCC patients with or without chemotherapy.

External Beam Radiotherapy for Hepatocellular Carcinoma: a Review of the Current Guidelines in the East and the West

The incidence of hepatocellular carcinoma (HCC) is geographically heterogeneous depending on the underlying liver disease. Moreover, the decisions and recommendations about standard treatments differ between countries, especially between the East and the West. Because of the complexity of treatment decisions for the management of HCC, a multidisciplinary approach is recommended to maximize the therapeutic efficacy. External beam radiotherapy (RT) has been increasingly used to manage HCC when recommended treatments cannot be applied in real-world clinical practice. However, Western guidelines for the management of HCC do not recommend RT as a treatment option due to the lack of clinical evidence. RT has often been used more in Eastern countries than in Western countries; hence, it is necessary to review both Eastern and Western guidelines for HCC treatment regarding the recommendations about RT. In this study, the comments and potential roles of external beam RT are summarized from several treatment guidelines for the management of HCC.

Application of M1 macrophage as a live vector in delivering nanoparticles for in vivo photothermal treatment

Introduction

To enhance photothermal treatment (PTT) efficiency, a delivery method that uses cell vector for nanoparticles (NPs) delivery has drawn attention and studied widely in recent years.

Objectives

In this study, we demonstrated the feasibility of M1 activated macrophage as a live vector for delivering NPs and investigated the effect of NPs loaded M1 stimulated by Lipopolysaccharide on PTT efficiency in vivo.

Methods

M1 was used as a live vector for delivering NPs and further to investigate the effect of NPs loaded M1 on PTT efficiency. Non-activated macrophage (MФ) was stimulated by lipopolysaccharide (LPS) into M1 and assessed for tumor cell phagocytic capacity towards NPs

Results

We found M1 exhibited a 20-fold higher uptake capacity of NPs per cell volume and 2.9-fold more active infiltration into the tumor site, compared with non-activated macrophage MФ. We injected M1 cells peritumorally and observed that these cells penetrated into the tumor mass within 12 h. Then, we conducted PTT using irradiation of a near-infrared laser for 1 min at 1 W/cm². As a result, we confirmed that using M1 as an active live vector led to a more rapid reduction in tumor size within 1 day indicating that the efficacy of PTT with NPs-loaded M1 is higher than that with NPs-loaded MФ.

Conclusion

Our study demonstrated the potential role of M1 as a live vector for enhancing the feasibility of PTT in cancer treatment.

Axitinib in combination with radiotherapy for advanced hepatocellular carcinoma: a phase I clinical trial

BACKGROUND

To investigate maximum tolerated dose (MTD) of axitinib, a selective vascular endothelial growth factor receptor 1-3 inhibitor, in combination with radiotherapy (RT) for advanced hepatocellular carcinoma (HCC).

METHODS

This phase I study followed the rule of traditional 3 + 3 design. Major eligibility included: (1) patients with advanced HCC unsuitable for surgery, radiofrequency ablation or transarterial chemoembolization, or who failed after prior local-regional treatment; (2) failure on sorafenib or no grant for sorafenib from health insurance system. Eligible patients with advanced HCC received axitinib for total 8 weeks during and after RT. Three cohorts with axitinib dose escalation were planned: 1 mg twice daily (level I), 2 mg twice daily (level II) and 3 mg twice daily (level III). The prescribed doses of RT ranged from 37.5 to 67.5 Gy in 15 fractions to liver tumor(s) and were determined based on an upper limit of mean liver dose of 18 Gy (intended isotoxic RT for normal liver). The primary endpoint was MTD of axitinib in combination with RT. The secondary endpoints included overall response rate (ORR), RT in-field response rate, acute and late toxicities, overall survival (OS) and progression free survival (PFS).

RESULTS

Total nine eligible patients received axitinib dose levels of 1 mg twice daily (n = 3), 2 mg twice daily (n = 3) and 3 mg twice daily (n = 3). Dose-limiting toxicity (DLT) did not occur in the 3 cohorts; the MTD was defined as 3 mg twice daily in this study. ORR was 66.7%, including 3 complete responses and 3 partial responses, at 3 months after treatment initiation. With a median follow-up of 16.6 months, median OS was not reached, 1-year OS was 66.7%, and median PFS was 7.4 months.

CONCLUSIONS

Axitinib in combination with RT for advanced HCC was well tolerated with an axitinib MTD of 3 mg twice daily in this study. The outcome analysis should be interpreted with caution due to the small total cohort. Trial registration ClinicalTrials.gov (Identifier: NCT02814461), Registered June 27, 2016-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02814461.

Long-Term Results of High-Dose 2-Fraction Carbon Ion Radiation Therapy for Hepatocellular Carcinoma

Purpose

Carbon ion beams have several physical and biological advantages compared with conventional radiation for cancer therapy. The objective of this study is to evaluate the safety and effectiveness of 2-fraction carbon ion radiation therapy (CIRT) in patients with hepatocellular carcinoma (HCC).

Methods and Materials

Between December 2008 and March 2013, 57 patients with localized HCC were treated with CIRT at a total dose of 45 Gy (relative biological effectiveness) in 2 fractions and retrospectively analyzed after long-term observation. The main endpoints of this study were treatment-related toxicity and local tumor control. Toxicity was assessed using the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0. Changes in the Child-Pugh score from before to after CIRT were also examined to evaluate hepatic toxicity. Local control was defined as no progression of the irradiated lesion according to the modified Response Evaluation Criteria in Solid Tumors.

Results

The median age of the patients was 75 years (range, 49-89 years). Of these patients, 41 had a newly diagnosed lesion, and 16 had residual or recurrent lesions after previous treatments. The median follow-up duration was 54 months (range, 7-103 months). All surviving patients were followed for more than 51 months. Two patients experienced grade 3 acute skin reactions, but no other grade 3 or higher toxicities were observed in any organ. No patient exhibited an increase in the Child-Pugh score of 2 or more points after CIRT. The local tumor control rates at 1, 3, and 5 years were 98%, 91%, and 91% after CIRT, respectively. All lesions that failed to respond to previous treatments were successfully controlled by CIRT. The 1-, 3-, and 5-year overall survival rates were 97%, 67%, and 45%, respectively.

Conclusions

Two-fraction CIRT was a well-tolerated and effective treatment for patients with HCC.

Berberine-loaded Janus gold mesoporous silica nanocarriers for chemo/radio/photothermal therapy of liver cancer and radiation-induced injury inhibition

Background: The combination of chemotherapy with radiotherapy serves as a common therapeutic strategy in clinics. However, it is unsatisfactory due to its poor therapeutic efficiency and severe side-effects originating from chemotherapy-exerted systemic toxicity as well as radiation-induced injury. Purpose: Hence, Berberine (Ber), an isoquinolin alkaloid with low toxicity and protective effects against radiotherapy, was used as a novel chemotherapeutic agent for chemo-radiotherapy of liver cancer. Patients and methods: We preloaded Ber into folic acid targeting Janus gold mesoporous silica nanocarriers (FA-JGMSNs) for overcoming the poor bioavailability of Ber. Furthermore, FA-JGMSNs were not only employed as radiosensitizers for expanding radiotherapeutic effect, but also used as photothermal agents for supplementing chemo-radiotherapeutic effect by local photothermal therapy. Results: In vitro and in vivo experiemtal results demonstrated the highly efficient anti-tumor effect, good biosafety as well as the effective protection of normal tissue of this nanoplatform. Conclusion: Based on its superb performance, we believe our work provided a feasible strategy for triple-therapies of liver cancer.

Transcatheter arterial chemoembolisation followed by three-dimensional conformal radiotherapy versus transcatheter arterial chemoembolisation alone for primary hepatocellular carcinoma in adults

BACKGROUND

Hepatocellular carcinoma, also called malignant hepatoma, is a primary malignancy of the liver. Despite regular surveillance conducted in high-risk populations, most people with hepatocellular carcinoma are diagnosed at an advanced stage. Consequently, only a minority of people with the disease are suitable for surgical resection when diagnosed.

OBJECTIVES

To compare the beneficial and harmful effects of transcatheter arterial chemoembolisation (TACE) followed by three-dimensional conformal radiotherapy (3-DCRT) versus TACE alone in adults with primary hepatocellular carcinoma, considered unsuitable for surgical resection.

SEARCH METHODS

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE, Embase, LILACS, Science Citation Index Expanded, and Conference Proceedings Citation Index - Science up to 31 May 2018. We checked reference lists for all included studies and related reviews for further relevant articles.

SELECTION CRITERIA

We included all randomised clinical trials comparing TACE followed by 3-DCRT versus TACE alone in people with primary hepatocellular carcinoma.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as suggested by Cochrane. We presented the results of the fixed-effect model in the absence of statistical heterogeneity. Otherwise, we reported the results from the random-effects model meta-analysis. We assessed risk of bias of the included trials using bias risk domains and presented the review results incorporating the methodological quality of the trials using GRADE. Our main conclusions were based on the analysis up to three years' follow-up.

MAIN RESULTS

We identified eight randomised clinical trials (632 participants) that fulfilled our inclusion criteria. All eight trials were at high risk of bias, and we rated the evidence as low to very low certainty. The mean age ranged from 16 years to 78 years. The proportion of men ranged from 60% to 75% and the proportion of people with stage III primary hepatocellular carcinoma ranged from 22% to 85%. The median follow-up duration was 12 months (2 months to 38 months).TACE followed by 3-DCRT compared with TACE alone may have reduced all-cause mortality at three years' follow-up (risk ratio (RR) 0.80, 95% confidence interval (CI) 0.73 to 0.88; 552 participants; 7 trials; low-certainty evidence). TACE followed by 3-DCRT compared with TACE alone may reduce the proportion of participants without tumour response (complete response plus partial response) (RR 0.49, 95% CI 0.39 to 0.61; 632 participants; 8 trials; low-certainty evidence). Data, from one trial on health-related quality of life, favoured the TACE followed by 3-DCRT group, but the provided data were ill-defined (very low-certainty evidence). None of the trials reported serious adverse events. The results on non-serious adverse events were as follows: TACE followed by 3-DCRT compared with TACE alone showed no difference in the results for proportion of participants with leukopenia (RR 1.12, 95% CI 0.92 to 1.34; 438 participants; 5 trials; very low-certainty evidence) and serum transaminases elevation (RR 1.67, 95% CI 0.66 to 4.27; 280 participants; 4 trials; very low-certainty evidence). However, the proportion of participants with total bilirubin elevation was larger in the TACE followed by 3-DCRT group than in the TACE alone group (RR 2.69, 95% CI 1.34 to 5.40; 172 participants; 2 trials; very low-certainty evidence). The rate of participants with serum alpha-fetoprotein (AFP) without decline or normalisation was significantly lower in the TACE followed by 3-DCRT group than in the TACE group, but these data were from one trial only (Chi² = 7.24, P = 0.007; very low-certainty evidence).

AUTHORS' CONCLUSIONS

TACE followed by 3-DCRT may be associated with lower all-cause mortality and increased tumour response, despite the increased toxicity expressed by a higher rise of total bilirubin. Our review findings should be considered with caution because of the methodological weaknesses in the included trials, resulting in low- to very low-certainty evidence. Data on serious adverse events and health-related quality of life are lacking. We are also very much uncertain in the results of the reported non-serious adverse events. High-quality trials are needed to assess further the role of TACE followed by 3-DCRT for unresectable hepatocellular carcinoma.

Strategic application of radiotherapy for hepatocellular carcinoma

With increasing clinical use, radiotherapy (RT) has been considered reliable and effective method for hepatocellular carcinoma (HCC) treatment, depending on extent of disease and patient characteristics. RT for HCC can improve therapeutic outcomes through excellent local control, downstaging, conversion from unresectable to resectable status, and treatments of unresectable HCCs with vessel invasion or multiple intrahepatic metastases. In addition, further development of modern RT technologies, including image-guided radiotherapy (IGRT), intensity-modulated radiotherapy (IMRT), and stereotactic body radiotherapy, has expanded the indication of RT. An essential feature of IGRT is that it allows image guidance therapy through in-room images obtained during radiation delivery. Compared with 3D-conformal RT, distinctions of IMRT are inverse treatment planning process and use of a large number of treatment fields or subfields, which provide high precision and exquisitely conformal dose distribution. These modern RT techniques allow more precise treatment by reducing inter- and intra-fractional errors resulting from daily changes and irradiated dose at surrounding normal tissues. More recently, particle therapy has been actively investigated to improve effectiveness of RT. This review discusses modern RT strategies for HCC, as well as optimal selection of RT in multimodal approach for HCC.

Targeting histone deacetylase 4/ubiquitin-conjugating enzyme 9 impairs DNA repair for radiosensitization of hepatocellular carcinoma cells in mice

Several strategies to improve the efficacy of radiation therapy against hepatocellular carcinoma (HCC) have been investigated. One approach is to develop radiosensitizing compounds. Because histone deacetylase 4 (HDAC4) is highly expressed in liver cancer and known to regulate oncogenesis through chromatin structure remodeling and controlling protein access to DNA, we postulated that HDAC4 inhibition might enhance radiation's effect on HCC cells. HCC cell lines (Huh7 and PLC5) and an ectopic xenograft were pretreated with HDAC inhibitor or short hairpin RNA to knock down expression of HDAC4 and then irradiated (2.5-10.0 Gy). We evaluated cell survival by a clonogenic assay; apoptosis by Annexin V immunofluorescence; γH2AX, Rad51, and HDAC4 by immunofluorescence staining; HDAC4, Rad51, and ubiquitin-conjugating enzyme 9 (Ubc9) in HCC cell nuclei by cell fractionation and confocal microscopy; physical interaction between HDAC4/Rad51/Ubc9 by immunoprecipitation; and the downstream targets of HDAC4 knockdown by immunoblotting. Both HDAC4 knockdown and HDAC inhibitor enhanced radiation-induced cell death and reduced homologous recombination repair of DNA double-strand breaks and protein kinase B activation, leading to increased apoptosis. HDAC4 knockdown with or without an HDAC inhibitor significantly delayed tumor growth in a radiation-treated xenograft model. Radiation stimulated nuclear translocation of Rad51 in an HDAC4-dependent manner and the binding of Ubc9 directly to HDAC4, which led to Ubc9 acetylation. Moreover, these effects were accompanied by HDAC4/Ubc9/Rad51 complex dissociation through inhibiting nuclear translocation. Conclusion: HDAC4 signaling blockade enhances radiation-induced lethality in HCC cells and xenografts. These findings raise the possibility that HDAC4/Ubc9/Rad51 complex in DNA repair may be a target for radiosensitization of HCC. (Hepatology 2018;67:586-599).

Janus Gold Nanoplatform for Synergetic Chemoradiotherapy and Computed Tomography Imaging of Hepatocellular Carcinoma

There is a pressing need to develop nanoplatforms that integrate multimodal therapeutics to improve treatment responses and prolong the survival of patients with unresectable hepatocellular carcinoma (HCC). Mesoporous silica-coated gold nanomaterials have emerged as a novel multifunctional platform combining tunable surface plasmon resonance and mesoporous properties that exhibit multimodality properties in cancer theranostics. However, their reduced radiation-absorption efficiency and limited surface area hinder their further radiochemotherapeutic applications. To address these issues, we designed Janus-structured gold-mesoporous silica nanoparticles using a modified sol-gel method. This multifunctional theranostic nanoplatform was subsequently modified via the conjugation of folic acid for enhanced HCC targeting and internalization. The loaded anticancer agent doxorubicin can be released from the mesopores in a pH-responsive manner, facilitating selective and safe chemotherapy. Additionally, the combination of chemotherapy and radiotherapy induced synergistic anticancer effects in vitro and exhibited remarkable inhibition of tumor growth in vivo along with significantly reduced systematic toxicity. Additionally, the Janus NPs acted as targeted computed tomography (CT)-imaging agents for HCC diagnosis. Given their better performance in chemoradiotherapy and CT imaging as compared with that of their core-shell counterparts, this new nanoplatform designed with dual functionalities provides a promising strategy for unresectable HCC theranostics.

Management consensus guideline for hepatocellular carcinoma: 2016 updated by the Taiwan Liver Cancer Association and the Gastroenterological Society of Taiwan

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortality in Taiwan. To help clinical physicians to manage patients with HCC, the Taiwan Liver Cancer Association and the Gastroenterological Society of Taiwan produced the management consensus guideline for HCC.

METHODS

The recommendations focus on nine important issues on management of HCC, including surveillance, diagnosis, staging, surgery, local ablation, transarterial chemoembolization/transarterial radioembolization/hepatic arterial infusion chemotherapy, systemic therapy, radiotherapy, and prevention.

RESULTS

The consensus statements were discussed, debated and got consensus in each expert team. And then the statements were sent to all of the experts for further discussion and refinement. Finally, all of the experts were invited to vote for the statements, including the level of evidence and recommendation.

CONCLUSION

With the development of the management consensus guideline, HCC patients could benefit from the optimal therapeutic modality.

Long-term survival analysis in combined transarterial embolization and stereotactic body radiation therapy versus stereotactic body radiation monotherapy for unresectable hepatocellular carcinoma >5 cm

BACKGROUND

The survival following transarterial chemoembolization (TACE) alone is still low in unresectable hepatocellular carcinoma (HCC) with almost patients developing disease progression after treatment. There is need to investigate additional therapeutic options that would intensify the initial response to TACE. The present study was to retrospectively compare the outcome and evaluate the prognostic factors of stereotactic body radiation therapy (SBRT) alone or as an adjunct to transarterial embolization (TAE) or TACE in the treatment of HCC >5 cm.

METHODS

From January 2011 to April 2015, 77 patients received SBRT followed by TAE or TACE (TAE/TACE + SBRT group) and 50 patients received SBRT alone (SBRT group). The dose of SBRT was 30-50 Gy which was prescribed in 3-5 fractions. Eligibility criteria were: a longest tumor diameter >5.0 cm and Child-Turcotte-Pugh (CTP) Class A or B. Exclusion criteria included tumor thrombus, lymph node involvement and extrahepatic metastasis.

RESULTS

The median follow-up period was 20.5 months. Median tumor size was 8.5 cm (range, 5.1-21.0 cm). Median overall survival (OS) in the TAE/TACE + SBRT group was 42.0 months versus 21.0 months in the SBRT group. The 1-, 3- and 5-year OS was 75.5, 50.8, and 46.9 % in the TAE/TACE + SBRT group and was 62.4, 32.9, and 32.9 % in the SBRT group, respectively (P = 0.047). The 1-, 3- and 5-year distant metastasis-free survival (DMFS) was 66.3, 44.3, and 40.6 % in the TAE/TACE + SBRT group and was 56.8, 26.1, and 17.4 % in the SBRT group, respectively (P = 0.049). The progression-free survival (PFS) and local relapse-free survival (LRFS) were not significantly different between the two groups. In the entire patient population, a biologically effective dose (BED₁₀) ≥100 Gy and an equivalent dose in 2 Gy fractions (EQD₂) ≥74 Gy were significant prognostic factors for OS, PFS, LRFS and DMFS.

CONCLUSIONS

SBRT combined with TAE/TACE may be an effective complementary treatment approach for HCC >5 cm in diameter. BED₁₀ ≥100 Gy and EQD₂ ≥74 Gy should receive more attention when the SBRT plan is designed.

Technical advances in external radiotherapy for hepatocellular carcinoma

Radiotherapy techniques have substantially improved in the last two decades. After the introduction of 3-dimensional conformal radiotherapy, radiotherapy has been increasingly used for the treatment of hepatocellular carcinoma (HCC). Currently, more advanced techniques, including intensity-modulated radiotherapy (IMRT), stereotactic ablative body radiotherapy (SABR), and charged particle therapy, are used for the treatment of HCC. IMRT can escalate the tumor dose while sparing the normal tissue even though the tumor is large or located near critical organs. SABR can deliver a very high radiation dose to small HCCs in a few fractions, leading to high local control rates of 84%-100%. Various advanced imaging modalities are used for radiotherapy planning and delivery to improve the precision of radiotherapy. These advanced techniques enable the delivery of high dose radiotherapy for early to advanced HCCs without increasing the radiation-induced toxicities. However, as there have been no effective tools for the prediction of the response to radiotherapy or recurrences within or outside the radiation field, future studies should focus on selecting the patients who will benefit from radiotherapy.

Sonic Hedgehog inhibition as a strategy to augment radiosensitivity of hepatocellular carcinoma

BACKGROUND AND AIM

Sonic Hedgehog (SHH) is a regulator in tumorigenesis of hepatocellular carcinoma (HCC). This study aimed to determine whether radiation-induced SHH signaling occurs in HCC and whether SHH inhibitor acts as a radiosensitizer.

METHODS

The in vitro effects of combining SHH ligand (recombinant human SHH) or inhibitor (cyclopamine) with irradiation were evaluated in the human HCC cell lines, Huh-7 and PLC/PRF/5, and murine cell line BNL. Cell survival and apoptosis were measured using a colony formation assay, annexin-V staining, and poly (ADP-ribose) polymerase activation. Western blotting and immunofluorescence staining were used to detect protein expression. The in vivo response to radiotherapy and/or cyclopamine was tested in BALB/c mice bearing an orthotopic allogeneic tumor.

RESULTS

Treatment of HCC cells with irradiation and SHH ligand had a protective effect on clonogenic cell survival. Treatment with irradiation and cyclopamine was a more potent inhibitor of cell proliferation than either modality alone. The antiproliferative activity of cyclopamine was attributable to apoptosis induction. Radiation dose-dependently upregulated the expression of Gli-1 (a transcription factor induced by SHH), and this effect was observed mainly in the nucleus. When combined with cyclopamine, irradiation inhibited Gli-1 and increased DNA double-strand breakage. Radiotherapy increased SHH and Gli-1 expression in allogeneic tumor. When compared with radiotherapy alone, cyclopamine with radiotherapy reduced the mean tumor size of orthotopic tumors by 67% (P < 0.05).

CONCLUSION

Combining an SHH inhibitor with radiotherapy may enhance HCC cell and orthotopic tumor radiosensitivity.

Targeting Phosphatidylinositide3-Kinase/Akt pathway by BKM120 for radiosensitization in hepatocellular carcinoma

Tumor control of hepatocellular carcinoma by radiotherapy remains unsatisfactory. The phosphatidylinositol 3-kinase (PI3K)/Akt pathway plays a critical role in inhibiting cancer cell death. Elevated PI3K/Akt activity is associated with increased cellular resistance to irradiation. Our aim was to determine whether the inhibition of PI3K/Akt activity by a PI3K inhibitor, BKM120, contributes to the increased sensitivity of liver cancer cells to irradiation. The hepatocellular carcinoma cell lines (Huh7 and BNL) were used to evaluate the in vitro synergism between BKM120 and irradiation. Balb/c mice bearing ectopic BNL xenografts were treated with BKM120 and/or radiotherapy to assess the in vivo response. BKM120 increased cell killing by radiation, increased the expression of apoptotic markers, and suppressed the repair of radiation-induced DNA double-strand breaks. BKM120 pretreatment inhibited radiation-induced Akt phosphorylation and enhanced the tumor-suppressive effect and radiation-induced tumor cell apoptosis in ectopic xenografts. Inhibition of mTOR phosphorylation by rapamycin enhanced the radiosensitivity of BKM120-treated hepatocellular carcinoma cells. The synergism between BKM120 and irradiation likely inhibits the activation of Akt by radiation, leading to increased cell apoptosis and suppression of DNA-double-strand breaks repair in hepatocellular carcinoma cells. These data suggest that the BKM120/radiation combination may be a strategy worthy of clinical trials.

The comparison of outcomes between hypofractionated and conventional 3D-CRT regimens used in combination with TACE as first-line treatment of advanced hepatocellular carcinoma

Treatment of primary hepatocellular carcinoma (HCC) with transcatheter hepatic arterial chemoembolization (TACE) and three-dimensional conformal radiotherapy (3D-CRT) achieves good short-term but poor long-term survival. We retrospectively assessed whether outcomes differ between hypofractionated and conventional 3D-CRT regimens. Patients were treated in our institution between June 2005 and October 2009. All patients received two cycles of TACE followed by either hypofractionated 3D-CRT (6-8 Gy fractions for 3-4 weeks to 48-64 Gy) or conventional 3D-CRT (2 Gy fractions for 6-7 weeks to 60-70 Gy) 4 weeks later. We assessed data from 110 patients (55 in each 3D-CRT group). Overall response rates were similar in the two groups. Acute adverse event rates were not significantly higher in the hypofractionated 3D-CRT group than in the conventional 3D-CRT group; two patients and one patient, respectively, died of late radiation-induced liver failure. Overall survival at 1 year was 83.6 % in the hypofractionated 3D-CRT group versus 68.8 % in the conventional 3D-CRT group (P = 0.019), and at 3 years, it was 31.7 versus 13.9 % (P = 0.004). Median survival was 27.97 versus 16.13 months (P = 0.002). Hypofractionated 3D-CRT seemed to provide better overall survival than conventional 3D-CRT regimens combined with TACE as a first-line treatment for advanced HCC.

Role of radiotherapy in the management of hepatocellular carcinoma: A systematic review

Many patients with hepatocellular carcinoma (HCC) present with advanced disease, not amenable to curative therapies such as surgery, transplantation or radiofrequency ablation. Treatment options for this group of patients include transarterial chemoembolization (TACE) and radiation therapy. Especially TACE, delivering a highly concentrated dose of chemotherapy to tumor cells while minimizing systemic toxicity of chemotherapy, has given favorable results on local control and survival. Radiotherapy, as a therapeutic modality of internal radiation therapy with radioisotopes, has also achieved efficacious tumor control in advanced disease. On the contrary, the role of external beam radiotherapy for HCC has been limited in the past, due to the low tolerance of surrounding normal liver parenchyma. However, technological innovations in the field of radiotherapy treatment planning and delivery, have provided the means of delivering radical doses to the tumor, while sparing normal tissues. Advanced and highly conformal radiotherapy approaches such as stereotactic body radiotherapy and proton therapy, evaluated for efficacy and safety for HCC, report encouraging results. In this review, we present the role of radiotherapy in hepatocellular carcinoma patients not suitable for radical treatment.

Curative effect of stereotactic body radiotherapy on hepatic hilar carcinoma

This study was conducted to investigate the effect of stereotactic body radiotherapy (SBRT) on hepatic hilar tumors. Between October, 2006 and October, 2012, we analyzed 63 unresectable hepatic hilar tumors that were treated by SBRT at the Department of Radiation Oncology, 323 Hospital of the People's Liberation Army, Xi'an, China. The patients received a total radiation dose of 45 Gy (range, 44-48 Gy) with a dose fractionation of 3-6 Gy/fx, administered for a total of 9-12 times, 2-5 times/week. At 1 and 3 months we evaluated therapeutic efficacy and 1- and 2-year survival rate. At 1 month, the patients exhibiting complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD) were 15 (23.8%), 34 (54.0%), 11 (17.5%) and 3 (4.7%), respectively. At 3 months, the number of cases with CR, PR, SD and PD was 22 (34.9%), 32 (50.8%), 3 (4.8%) and 6 (9.5%), respectively. The total effective rate, defined as CR + PR, was 85.7% (54/63). The number of patients with a tumor diameter of ≤5 cm in the CR, PR, SD and PD groups was 13 (72.2%), 4 (22.2%), 1 (5.6%) and 0 (0.0%), respectively. The number of patients with a tumor diameter of >5 cm in the CR, PR, SD and PD groups was 9 (20.0%), 28 (62.2%), 6 (13.3%) and 2 (4.5%), respectively. The 1-year survival rate of patients with a tumor diameter >5 cm was 71.4% (45/63) and the 2-year survival rate was 42.9% (27/63). In conclusion, SBRT appears to be a safe and effective treatment for hepatic hilar tumors.

Phase 2 study of combined sorafenib and radiation therapy in patients with advanced hepatocellular carcinoma

PURPOSE

This phase 2 study evaluated the efficacy of radiation therapy (RT) with concurrent and sequential sorafenib therapy in patients with unresectable hepatocellular carcinoma (HCC).

METHODS AND MATERIALS

Forty patients with unresectable HCC unfit for transarterial chemoembolization were treated with RT with concurrent and sequential sorafenib. Sorafenib was administered from the commencement of RT at a dose of 400 mg twice daily and continued to clinical or radiologic progression, unacceptable adverse events, or death. All patients had underlying Child-Pugh A cirrhosis. The maximal tumor diameter ranged from 3.0 cm to 15.5 cm. Coexisting portal vein thrombosis was found in 24 patients and was irradiated simultaneously. The cumulative RT dose ranged from 40 Gy to 60 Gy (median, 50 Gy). Image studies were done 1 month after RT and then every 3 months thereafter.

RESULTS

Thirty-three (83%) completed the allocated RT. During RT, the incidence of hand-foot skin reactions ≥ grade 2 and diarrhea were 37.5% and 25%, respectively, and 35% of patients had hepatic toxicities grade ≥2. Twenty-two (55.0%) patients achieved complete or partial remission at the initial assessment, and 18 (45%) had stable or progressive disease. The 2-year overall survival and infield progression-free survival (IFPS) were 32% and 39%, respectively. A Cancer of the Liver Italian Program (CLIP) score ≥2 was associated with an inferior outcome in overall survival. Six patients (15%) developed treatment-related hepatic toxicity grade ≥3 during the sequential phase, and 3 of them were fatal.

CONCLUSIONS

When RT and sorafenib therapy were combined in patients with unresectable HCC, the initial complete or partial response rate was 55% with a 2-year IFPS of 39%. A CLIP score ≥2 was associated with an inferior outcome in overall survival. Hepatic toxicities are a major determinant of the safety; the combination should be used with caution and needs further investigation.

Risk of secondary cancers from scattered radiation during intensity-modulated radiotherapies for hepatocellular carcinoma

PURPOSE

To evaluate and compare the risks of secondary cancers from therapeutic doses received by patients with hepatocellular carcinoma (HCC) during intensity-modulated radiotherapy (IMRT), volumetric arc therapy (VMAT), and tomotherapy (TOMO).

METHODS

Treatments for five patients with hepatocellular carcinoma (HCC) were planned using IMRT, VMAT, and TOMO. Based on the Biological Effects of Ionizing Radiation VII method, the excess relative risk (ERR), excess absolute risk (EAR), and lifetime attributable risk (LAR) were evaluated from therapeutic doses, which were measured using radiophotoluminescence glass dosimeters (RPLGDs) for each organ inside a humanoid phantom.

RESULTS

The average organ equivalent doses (OEDs) of 5 patients were measured as 0.23, 1.18, 0.91, 0.95, 0.97, 0.24, and 0.20 Gy for the thyroid, lung, stomach, liver, small intestine, prostate (or ovary), and rectum, respectively. From the OED measurements, LAR incidence were calculated as 83, 46, 22, 30, 2 and 6 per 10(4) person for the lung, stomach, normal liver, small intestine, prostate (or ovary), and rectum.

CONCLUSIONS

We estimated the secondary cancer risks at various organs for patients with HCC who received different treatment modalities. We found that HCC treatment is associated with a high secondary cancer risk in the lung and stomach.

Significance of an increase in the Child-Pugh score after radiotherapy in patients with unresectable hepatocellular carcinoma

Background

We attempted to analyze the effects of an increase in the Child-Pugh (CP) score on the overall survival of patients with unresectable hepatocellular carcinoma (HCC) after radiotherapy (RT).

Methods

From March 2006 to February 2012, 103 patients received RT using the TomoTherapy Hi-Art at Incheon St. Mary’s Hospital and Seoul St. Mary’s Hospital. The dose per fraction was 1.8–5 Gy, and the total dose was 40–60 Gy (median, 50 Gy). We considered an increase of at least 2 points in the CP score within 3 months after RT to be clinically important radiation-induced hepatic toxicity and analyzed the effects of an increased CP score on overall survival.

Results

The median follow-up duration was 11.6 months (range, 3.5–85.3 months). The median survival time was 11.6 months. In multivariate analysis, planning target volume and an increase in the CP score after RT were found to be a statistically significant factors (p = 0.010 and 0.015, respectively). In a comparison of cases with and without an increase in the CP score, there was an 11.0-month difference in the median survival time (6.9 vs. 17.9 months), and the relative risk of mortality was 1.8.

Conclusion

An increase of at least 2 points in the CP score within 3 months of RT completion is an important on-treatment factor that affects overall survival. To minimize such increases, careful patient selection and a more sophisticated radiation treatment plan are imperative.

Simultaneous integrated boost-intensity modulated radiation therapy for inoperable hepatocellular carcinoma

PURPOSE

The aim of this work was to evaluate the clinical efficacy and safety of simultaneous integrated boost-intensity modulated radiation therapy (SIB-IMRT) in patients with inoperable hepatocellular carcinoma (HCC).

METHODS AND MATERIALS

A total of 53 patients with inoperable HCC underwent SIB-IMRT using two dose-fractionation schemes, depending on the proximity of gastrointestinal structures. The 41 patients in the low dose-fractionation (LD) group, with internal target volume (ITV) < 1 cm from gastrointestinal structures, received total doses of 55 and 44 Gy in 22 fractions to planning target volume 1 (PTV1) and 2 (PTV2), respectively. The 12 patients in the high dose-fractionation (HD) group, with ITV ≥ 1 cm from gastrointestinal structures, received total doses of 66 and 55 Gy in 22 fractions to the PTV1 and PTV2, respectively.

RESULTS

Overall, treatment was well tolerated, with no grade > 3 toxicity. The LD group had larger sized tumors (median: 6 vs. 3.4 cm) and greater frequencies of vascular invasion (80.6 vs. 16.7 %) than patients in the HD group (p < 0.05 each). The median overall survival (OS) was 25.1 mKonzept ist machbar und sicheronths and the actuarial 2-year local progression-free survival (LPFS), relapse-free survival (RFS), and OS rates were 67.3, 14.7, and 54.7  %, respectively. The HD group tended to show better tumor response (100 vs. 62.2 %, p = 0.039) and 2-year LPFS (85.7 vs. 59  %, p = 0.119), RFS (38.1 vs. 7.3 %, p = 0.063), and OS (83.3 vs. 44.3 %, p = 0.037) rates than the LD group. Multivariate analysis showed that tumor response was significantly associated with OS.

CONCLUSION

SIB-IMRT is feasible and safe for patients with inoperable HCC.

Radiosensitization by combining an aurora kinase inhibitor with radiotherapy in hepatocellular carcinoma through cell cycle interruption

Radiotherapy has been integrated into the multimodal treatment of hepatocellular carcinoma (HCC), especially of localized hepatic tumor(s) refractory to conventional treatment. However, tumor control remains unsatisfactory mainly because of insufficient dose, and sublethally irradiated tumor may associate with metastasis. Our aim was to assess the effect of combining a molecularly targeted Aurora kinase inhibitor, VE-465, with radiotherapy in in vitro and in vivo models of human HCC. Human HCC cell lines (Huh7 and PLC-5) were used to evaluate the in vitro synergism of combining VE-465 with irradiation. Flow cytometry analyzed the cell cycle changes, while western blot investigated the protein expressions after the combined treatment. Severe combined immunodeficient (SCID) mice bearing ectopic and orthotopic HCC xenografts were treated with VE-465 and/or radiotherapy for the in vivo response. VE-465 significantly enhanced radiation-induced death in HCC cells by a mechanism involving the enhanced inhibition of histone H3 phosphorylation and interruption of cell cycle change. In SCID, mice bearing ectopic HCC xenografts, pretreatment with VE-465 (20 mg/kg/day × 9 days) significantly enhanced the tumor-suppressive effect of radiotherapy (5 Gy/day × 5 days) by 54.0%. A similar combinatorial effect of VE-465 and radiotherapy was observed in an orthotopic model of Huh7 tumor growth by 17.2%. In the orthotopic Huh7 xenografts, VE-465 significantly enhanced radiation-induced tumor growth suppression by a mechanism involving the increased apoptosis. VE-465 is a potent inhibitor of Aurora kinase with therapeutic value as a radiosensitizer of HCC.

Feasibility of sorafenib combined with local radiotherapy in advanced hepatocellular carcinoma

PURPOSE

Sorafenib is an effective systemic agent for advanced hepatocellular carcinoma. To increase its efficacy, we evaluated the feasibility and benefit of sorafenib combined with radiotherapy.

MATERIALS AND METHODS

From July 2007 to July 2011, 31 patients were treated with a daily dose of 800 mg of sorafenib and radiotherapy. Among them, 13 patients who received radiotherapy on the bone metastasis were excluded. Thirteen patients received 30-54 Gy of radiotherapy on the primary tumor (primary group) and 5 patients received 30-58.4 Gy on the measurable metastatic lesions (measurable metastasis group). Tumor responses at 1 month after the completion of radiotherapy and overall survival were evaluated.

RESULTS

The in-field response rate was 100% in the primary group and 60% in the measurable metastasis group. A decrease of more than 80% in the tumor marker α-fetoprotein was observed in 7 patients in the primary group (54%). Toxicities of grades 3-4 were hand-foot syndrome in 3 (17%) patients, duodenal bleeding in 1 (6%) patient, thrombocytopenia in 3 (17%) patients and elevation of aspartate transaminase in 1 (6%) patient. The median overall survival was 7.8 months (95% confidence interval, 3.0-12.6).

CONCLUSION

The combined treatment of sorafenib and radiotherapy was feasible and induced substantial tumor responses in the target lesions. The results of this study emphasize the importance of individualized approach in the management of advanced hepatocellular carcinoma and encourage the initiation of a controlled clinical trial.

Superior liver sparing by combined coplanar/noncoplanar volumetric-modulated arc therapy for hepatocellular carcinoma: a planning and feasibility study

Compared with step-and-shoot intensity-modulated radiotherapy (sIMRT) and tomotherapy, volumetric-modulated arc therapy (VMAT) allows additional arc configurations in treatment planning and noncoplanar (NC) delivery. This study was first to compare VMAT planning with sIMRT planning, and the second to evaluate the toxicity of coplanar (C)/NC-VMAT treatment in patients with hepatocellular carcinoma (HCC). Fifteen patients with HCC (7 with left-lobe and 8 with right-lobe tumors) were planned with C-VMAT, C/NC-VMAT, and sIMRT. The median total dose was 49Gy (range: 40 to 56Gy), whereas the median fractional dose was 3.5Gy (range: 3 to 8Gy). Different doses/fractionations were converted to normalized doses of 2Gy per fraction using an α/β ratio of 2.5. The mean liver dose, volume fraction receiving more than 10Gy (V10), 20Gy (V20), 30Gy (V30), effective volume (Veff), and equivalent uniform dose (EUD) were compared. C/NC-VMAT in 6 patients was evaluated for delivery accuracy and treatment-related toxicity. Compared with sIMRT, both C-VMAT (p = 0.001) and C/NC-VMAT (p = 0.03) had significantly improved target conformity index. Compared with C-VMAT and sIMRT, C/NC-VMAT for treating left-lobe tumors provided significantly better liver sparing as evidenced by differences in mean liver dose (p = 0.03 and p = 0.007), V10 (p = 0.003 and p = 0.009), V20 (p = 0.006 and p = 0.01), V30 (p = 0.02 and p = 0.002), Veff (p = 0.006 and p = 0.001), and EUD (p = 0.04 and p = 0.003), respectively. For right-lobe tumors, there was no difference in liver sparing between C/NC-VMAT, C-VMAT, and sIMRT. In all patients, dose to more than 95% of target points met the 3%/3mm criteria. All 6 patients tolerated C/NC-VMAT and none of them had treatment-related ≥ grade 2 toxicity. The C/NC-VMAT can be used clinically for HCC and provides significantly better liver sparing in patients with left-lobe tumors.

Sorafenib enhances radiation-induced apoptosis in hepatocellular carcinoma by inhibiting STAT3

PURPOSE

Hepatocellular carcinoma (HCC) is one of the most common and lethal human malignancies. Lack of efficient therapy for advanced HCC is a pressing problem worldwide. This study aimed to determine the efficacy and mechanism of combined sorafenib and radiation therapy treatment for HCC.

METHODS AND MATERIALS

HCC cell lines (PLC5, Huh-7, Sk-Hep1, and Hep3B) were treated with sorafenib, radiation, or both, and apoptosis and signal transduction were analyzed.

RESULTS

All 4 HCC cell lines showed resistance to radiation-induced apoptosis; however, this resistance could be reversed in the presence of sorafenib. Inhibition of phospho-STAT3 was found in cells treated with sorafenib or sorafenib plus radiation and subsequently reduced the expression levels of STAT3-related proteins, Mcl-1, cyclin D1, and survivin. Silencing STAT3 by RNA interference overcame apoptotic resistance to radiation in HCC cells, and the ectopic expression of STAT3 in HCC cells abolished the radiosensitizing effect of sorafenib. Moreover, sorafenib plus radiation significantly suppressed PLC5 xenograft tumor growth.

CONCLUSIONS

These results indicate that sorafenib sensitizes resistant HCC cells to radiation-induced apoptosis via downregulating phosphorylation of STAT3 in vitro and in vivo.

Biomarker studies on radiotherapy to hepatocellular carcinoma

Radiotherapy (RT) has been gradually integrated into the multimodality treatment for hepatocellular carcinoma (HCC). The various patterns of failure in HCC patients undergoing RT drive the need of effective biomarkers to guide treatment decisions. Limited numbers of biomarkers have been investigated in HCC, with even fewer of them for patients treated by RT. Serum or plasma biomarkers measured by enzyme-linked immunosorbent assay were the most common practice. Of particular interest are those biomarkers that are detectable early in the course of radiotherapy which correlated with ultimate clinical outcome. Functional magnetic resonance imaging (MRI) is increasingly used to evaluate the imaging pattern indicative of disease control following RT. Positron emission tomography shows that pre-RT standard uptake values associate with various types of recurrence after treatment. Proximity ligation assay (PLA) is evolving with the unique features of dual-probe identification, ligation and amplification to allow the small volume of serum/plasma samples for evaluating multiple biomarkers. We demonstrate the screening work of biomarkers by PLA with pre- and post-RT serum samples from HCC patients undergoing RT. Efforts are being made to search for the potential biomarkers for HCC patients treated by RT.

Dosimetric parameter predicting the deterioration of hepatic function after helical tomotherapy in patients with unresectable locally advanced hepatocellular carcinoma

BACKGROUND

The purpose of this study was to identify parameters capable of predicting the deterioration of hepatic function after helical tomotherapy in patients with unresectable locally advanced hepatocellular carcinoma.

METHODS

Between March 2006 and February 2012, 72 patients were eligible for this study. All patients received hypofractionated radiotherapy using the TomoTherapy Hi-Art (TomoTherapy, Madison, WI, USA) at Seoul St. Mary's Hospital and Incheon St. Mary's Hospital, the Catholic University of Korea. The radiation dose was a median 50 Gy (range: 40-50 Gy) in 10 fractions to 95% of the planning target volume. Radiation-induced hepatic toxicity was defined as an increase of at least 2 points in the Child-Pugh (CP) score within 3 months after completion of helical tomotherapy.

RESULTS

An increase of at least 2 points in the CP score occurred in 32 of the 72 patients (44.4%). Multivariate logistic regression analysis revealed that pretreatment CP class and V15Gy were significant parameters associated with an increase in CP score (p = 0.009 and p < 0.001, respectively). The area under receiver operating characteristic curve was 0.863 for V15Gy (p < 0.001). For V15Gy, with a cutoff value of 43.2%, the accuracy was 0.806 (58/72) with a sensitivity of 0.938 and a specificity of 0.725.

CONCLUSIONS

An increase of at least 2 points in the CP score is a radiation dose-limiting factor, and the non-target normal liver receiving a dose more than 15 Gy (V15Gy) should be <43.2% to reduce the risk of the deterioration of hepatic function.

Proton therapy for hepatocellular carcinoma

Proton radiotherapy has seen an increasing role in the treatment of hepatocellular carcinoma (HCC). Historically, external beam radiotherapy has played a very limited role in HCC due to a high incidence of toxicity to surrounding normal structures. The ability to deliver a high dose of radiation to the tumor is a key factor in improving outcomes in HCC. Advances in photon radiotherapy have improved dose conformity and allowed dose escalation to the tumor. However, despite these advances there is still a large volume of normal liver that receives a considerable radiation dose during treatment. Proton beams do not have an exit dose along the beam path once they enter the body. The inherent physical attributes of proton radiotherapy offer a way to maximize tumor control via dose escalation while avoiding excessive radiation to the remaining liver, thus increasing biological effectiveness. In this review we discuss the physical attributes and rationale for proton radiotherapy in HCC. We also review recent literature regarding clinical outcomes of using proton radiotherapy for the treatment of HCC.

Boron neutron capture therapy (BNCT) for liver metastasis: therapeutic efficacy in an experimental model

Boron neutron capture therapy (BNCT) was proposed for untreatable colorectal liver metastases. The present study evaluates tumor control and potential radiotoxicity of BNCT in an experimental model of liver metastasis. BDIX rats were inoculated with syngeneic colon cancer cells DHD/K12/TRb. Tumor-bearing animals were divided into three groups: BPA-BNCT, boronophenylalanine (BPA) + neutron irradiation; Beam only, neutron irradiation; Sham, matched manipulation. The total absorbed dose administered with BPA-BNCT was 13 ± 3 Gy in tumor and 9 ± 2 Gy in healthy liver. Three weeks post-treatment, the tumor surface area post-treatment/pre-treatment ratio was 0.46 ± 0.20 for BPA-BNCT, 2.7 ± 1.8 for Beam only and 4.5 ± 3.1 for Sham. The pre-treatment tumor nodule mass of 48 ± 19 mg fell significantly to 19 ± 16 mg for BPA-BNCT, but rose significantly to 140 ± 106 mg for Beam only and to 346 ± 302 mg for Sham. For both end points, the differences between the BPA-BNCT group and each of the other groups were statistically significant (ANOVA). No clinical, macroscopic or histological normal liver radiotoxicity was observed. It is concluded that BPA-BNCT induced a significant remission of experimental colorectal tumor nodules in liver with no contributory liver toxicity.

The significance of ICG-R15 in predicting hepatic toxicity in patients receiving radiotherapy for hepatocellular carcinoma

AIM

To evaluate whether the retention rate of indocyanine green 15 min after administration (ICG-R15) could predict radiation hepatotoxicity in patients treated with radiotherapy (RT) for hepatocellular carcinoma (HCC).

METHODS

We retrospectively reviewed data of 146 HCC patients treated with RT between February 1994 and December 2008. The ICG-R15 was measured within 1 month prior to the start of RT. Radiation hepatotoxicity was evaluated by incidence of radiation-induced liver disease (RILD) between 2 weeks and 3 months after completion of RT. We analysed the correlation between the incidence rate of RILD and the ICG-R15 before RT (pre-RT ICG-R15).

RESULTS

The classic and non-classic RILD occurred in 15 patients (10.3%): classic type in five patients (3.4%) and non-classic RILD in 10 patients (6.9%). A positive correlation was shown between the probability of RILD and increase in pre-RT ICG-R15 (P < 0.0001). Univariate analysis indicated that cut-off value of pre-RT ICG-R15 could predict RILD significantly. The incidence of RILD for the patients with 22% or higher pre-RT ICG-R15 levels was 40.7% as compared to 3.4% for those with levels lower than 22% (P < 0.0001). There was no clinical factor that significantly affected RILD in univariate analysis. Multivariate analysis indicated that the pre-RT ICG-R15 value was the only significant factor affecting RILD (P < 0.0001).

CONCLUSION

These results suggest that pre-RT ICG-R15 could be a useful factor in predicting radiation hepatotoxicity in HCC patients treated with RT.

Radiosensitizing effect of a phenylbutyrate-derived histone deacetylase inhibitor in hepatocellular carcinoma

PURPOSE

Radiotherapy is integrated into the multimodal treatment of localized hepatocellular carcinoma (HCC) refractory to conventional treatment. Tumor control remains unsatisfactory and the sublethal effect associates with secondary spread. The use of an effective molecularly targeted agent in combination with radiotherapy is a potential therapeutic approach. Our aim was to assess the effect of combining a phenylbutyrate-derived histone deacetylase (HDAC) inhibitor, AR-42, with radiotherapy in in vitro and in vivo models of human HCC.

METHODS AND MATERIALS

Human HCC cell lines (Huh-7 and PLC-5) were used to evaluate the in vitro synergism of combining AR-42 with irradiation. Flow cytometry analyzed the cell cycle changes, whereas Western blot investigated the protein expressions after the combined treatment. Severe combined immunodeficient (SCID) mice bearing ectopic and orthotopic HCC xenografts were treated with AR-42 and/or radiotherapy for the in vivo response.

RESULTS

AR-42 significantly enhanced radiation-induced cell death by the inhibition of the DNA end-binding activity of Ku70, a highly versatile regulatory protein for DNA repair, telomere maintenance, and apoptosis. In ectopic xenografts of Huh-7 and PLC-5, pretreatment with AR-42 significantly enhanced the tumor-suppressive effect of radiotherapy by 48% and 66%, respectively. A similar combinatorial effect of AR-42 (10 and 25 mg/kg) and radiotherapy was observed in Huh-7 orthotopic model of tumor growth by 52% and 82%, respectively. This tumor suppression was associated with inhibition of intratumoral Ku70 activity as well as reductions in markers of HDAC activity and proliferation, and increased apoptosis.

CONCLUSION

AR-42 is a potent, orally bioavailable inhibitor of HDAC with therapeutic value as a radiosensitizer of HCC.

Radiation therapy for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common malignancy worldwide, and its incidence is on the rise. The primary therapy is resection or liver transplant, but only a minority of patients present with resectable disease. Historically, radiotherapy has not played a significant role in the treatment of liver malignancies because of the low tolerance of the whole liver to radiation. With improvements in 3-dimensional conformal radiotherapy and intensity-modulated radiotherapy, higher doses of radiation can be delivered to target lesions with low doses to the noninvolved liver; thus, experience in the use of radiation for the treatment of focal HCC has increased. At the same time, our understanding of the relationships between radiation dose and volume and the risk of classic radiation-induced liver disease and other toxicities more likely to occur in HCC patients has improved considerably. These developments have led to a body of evidence that now supports the careful use of radiotherapy for unresectable HCC. The rationale for studying radiotherapy in a randomized trial is strong.

Radiotherapeutic strategies in the management of hepatocellular carcinoma

Although potentially curative therapies for hepatocellular carcinoma (HCC) are well established, they are offered only to a limited number of patients. For advanced HCC, sorafenib is now the treatment of choice. Radiotherapy technology has evolved remarkably during the past decade and can be precisely delivered, thereby permitting higher doses to the tumor and reduced doses to surrounding normal tissues. According to the Korean Liver Cancer Study Group (KLCSG) practice guidelines, radiation therapy is considered appropriate for unresectable, locally advanced HCC without extrahepatic metastasis, Child-Pugh class A or B, and tumors occupying less than two thirds of the liver with level II evidence. In this review, we discuss the radiotherapeutic strategies for each clinical setting in patients with HCC.

Radiation treatment outcomes for unresectable hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma is one of the most common cancers worldwide. Data regarding the use of radiotherapy is limited in patients from populations without endemic viral hepatitis. We examine the outcomes for patients treated with radiotherapy in the modern era at a single institution.

MATERIAL AND METHODS

A total of 29 patients with localized hepatocellular carcinoma treated from 2000-2010 were reviewed. Patients with metastatic disease at the time of radiation were excluded. Median radiation dose was 50 Gy (range 30 to 75 Gy) with a median biologically effective dose of 80.6 (range 60 to 138.6). Median tumor size at the time of radiation was 5.2 cm (range 2 to 25 cm).

RESULTS

Eighty three percent of all patients had either stable disease or a partial response to radiation, based on RECIST criteria. Median change in tumor size following radiation was -17% (range -73.5 to 177.8%). Estimated one-year overall survival and in-field progression-free survival rates for the study population were 56% and 79%, respectively. One-year overall survival in patients treated to a biologically effective dose <75 was significantly lower than in patients treated to a biologically effective dose ≥75 (18% vs. 69%). One-year in-field progression-free survival rate (60% vs. 88%) and biochemical progression-free survival duration (median 6.5 vs. 1.6 months) were also significantly improved in patients treated to a biologically effective dose ≥75. Grade 3 toxicity was seen in 13.8% of patients.

DISCUSSION

In a population without endemic viral hepatitis, unresectable hepatocellular carcinoma demonstrates significant response to radiotherapy with minimal toxicity. Furthermore, our findings suggest that increased biologically effective dose is associated with improved survival and local tumor control.

Radiotherapy plus transarterial chemoembolization for hepatocellular carcinoma invading the portal vein: long-term patient outcomes

PURPOSE

We have evaluated the clinical outcomes of patients after transarterial chemoembolization (TACE) and 3-dimensional conformal radiotherapy for hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT).

METHODS AND MATERIALS

A registry database of 412 patients treated with TACE and three-dimensional conformal radiotherapy for HCC with PVTT between August 2002 and August 2008 were analyzed retrospectively. The radiotherapy volume included the PVTT, with a 2- to 3-cm margin to cover adjacent HCC. Intrahepatic primary HCC was managed by TACE before or after radiotherapy.

RESULTS

Median patient age was 52 years old, and 88.1% of patients were male. Main or bilateral PVTT was observed in 200 (48.5%) patients. Median radiation dose was 40 Gy (range, 21-60 Gy) delivered in 2- to 5-Gy fractions. We found that 3.6% of patients achieved a complete response and that 24.3% of patients achieved a partial response. The response and progression-free rates of PVTT were 39.6% and 85.6%, respectively. Median patient survival was 10.6 months, and the 1- and 2-year survival rates were 42.5% and 22.8%, respectively. Significant independent variables associated with overall survival included advanced tumor stage, alpha-fetoprotein level, degree of PVTT, and response to radiotherapy. Forty-one patients (10.0%) showed grade 3-4 hepatic toxicity during or 3 months after completion of radiotherapy. Grades 2-3 gastroduodenal complications were observed in 15 patients (3.6%).

CONCLUSIONS

Radiotherapy is a safe and effective treatment for PVTT in patients with HCC. These results suggested that the combination of TACE and radiotherapy is a treatment option for relieving and/or stabilizing PVTT in patients with advanced HCC.

Stereotactic radiotherapy of hepatocellular carcinoma: preliminary results

Stereotactic radiotherapy (SRT) offers a treatment option for hepatocellular carcinoma (HCC) patients that are not eligible for surgery, embolization, chemotherapy, or radiofrequency ablation. We have evaluated the feasibility, tolerance and toxicity of SRT for 25 HCC patients who were not eligible for these other modalities. The patients (6 women and 19 men) were treated with CyberKnife stereotactic radiotherapy using respiratory motion tracking. All patients had liver cirrhosis with an Eastern Cooperative Oncology Group (ECOG) performance score of less than 2 and pre-treatment Child scores ranging from A5 to B9. A total dose of 45 Gy in three fractions of 15 Gy each was prescribed to the 80% isodose line (95% of the PTV received 45 Gy) and delivered to the target volume over 10 to 12 days. Overall the treatment was well tolerated with two Grade 3 acute toxicities and no acute Grade 4 toxicities. Late toxicity was minimal with all observed late toxicities occurring within the first six months of follow-up. Three hepatic recurrences at a distance from the target and one metastasis were observed. The actuarial 1- and 2-year local control rate was 95% (95% CI: 69-95%). At a median overall follow-up of 12,7 months (range, 1-24 months), six of the twenty-five (24%) patients have died. Overall actuarial survival at 1- and 2-years was 79% (95% CI: 52-92%) and 52% (95% CI: 19-78%), respectively. Our results suggest promising therapeutic efficacy and good clinical tolerance to CyberKnife SRT treatment for HCC patients not eligible for other treatment modalities.

Dosimetric predictor identification for radiation-induced liver disease after hypofractionated conformal radiotherapy for primary liver carcinoma patients with Child-Pugh Grade A cirrhosis

PURPOSE

Radiation-induced liver disease (RILD) is the most severe complication in liver cancer treatment. The aim of this study was to identify dosimetric predictors for RILD in primary liver carcinoma (PLC) patients with Child-Pugh Grade A cirrhosis after hypofractionated conformal radiotherapy (CRT).

METHODS AND MATERIALS

A total of 114 eligible patients (mean age 45 years old) were enrolled and treated. The mean gross tumor volume (GTV) was (378.3±308.1) cm(3). A median dose of 53 Gy was delivered to the PLC by hypofractionated CRT (three fractions/week) with a median fraction size of 4.6 Gy (range: 4-6 Gy).

RESULTS

Patients were followed up for 1-79 months (median 19 months) after the completion of irradiation. RILD was diagnosed in nine (7.9%) patients. Univariate analyses revealed that GTV and the percentage of normal liver volume receiving more than 5-40 Gy irradiations (V(5-40)) were related to the risk of developing RILD. Multivariate analyses demonstrated that only GTV and V(20) were independent predictors. Using V(20) as the predictor for RILD, the accuracy, sensitivity, and specificity was 76.3%, 88.9%, and 75.2%, respectively.

CONCLUSIONS

Our data suggest that V(20) is the unique significant dosimetric predictor for RILD risks in PLC patients with Child-Pugh Grade A cirrhosis after hypofractionated CRT.

Early three-dimensional conformal radiotherapy for patients with unresectable hepatocellular carcinoma after incomplete transcatheter arterial chemoembolization: a prospective evaluation of efficacy and toxicity

PURPOSE

We prospectively evaluated the efficacy and toxicity of early 3-dimensional conformal radiotherapy (3D-CRT) for patients with unresectable hepatocellular carcinoma (HCC) after incomplete transcatheter arterial chemoembolization (TACE).

METHODS

Patients with unresectable HCC who failed 1 or 2 courses of TACE were eligible for this study. Three dimensional-CRT was added for HCC with incomplete uptake of iodized oil. Between January 2006 and February 2007, 40 patients (43 lesions) were enrolled. TACE was performed by using Lipiodol and adriamycin, followed by Gelfoam embolization. Two cycles of TACE were performed in 24 patients (60%), whereas 16 patients (40%) underwent one cycle. The median dose of 54 Gy (3 Gy daily) was delivered with 3D-CRT. Tumor response was evaluated by changes in tumor size on serial computed tomography scans and toxicity was evaluated by the Common Terminology Criteria for Adverse Events v3.0.

RESULTS

An objective response was achieved in 27 of 43 lesions (62.8%), with a complete response in 9 lesions (20.9%) and partial response in 18 lesions (41.9%). The overall survival rate was 72.0% at 1 year and 45.6% at 2 years. There was no grade 3 or greater acute toxicity. Nine patients (22.5%) showed progression of the disease within the irradiated field during the follow-up and intrahepatic metastases developed in 16 patients (40.0%).

CONCLUSION

Early 3D-CRT for HCC unresponsive to 1 or 2 cycles of TACE resulted in a 62.8% tumor response rate and relatively high complete response rates (20.9%) with acceptable toxicity. This study shows that the application of 3D-CRT could be considered for patients with incomplete TACE.

Comparison of coplanar and noncoplanar intensity-modulated radiation therapy and helical tomotherapy for hepatocellular carcinoma

Background

To compare the differences in dose-volume data among coplanar intensity modulated radiotherapy (IMRT), noncoplanar IMRT, and helical tomotherapy (HT) among patients with hepatocellular carcinoma (HCC) and portal vein thrombosis (PVT).

Methods

Nine patients with unresectable HCC and PVT underwent step and shoot coplanar IMRT with intent to deliver 46 - 54 Gy to the tumor and portal vein. The volume of liver received 30Gy was set to keep less than 30% of whole normal liver (V30 < 30%). The mean dose to at least one side of kidney was kept below 23 Gy, and 50 Gy as for stomach. The maximum dose was kept below 47 Gy for spinal cord. Several parameters including mean hepatic dose, percent volume of normal liver with radiation dose at X Gy (Vx), uniformity index, conformal index, and doses to organs at risk were evaluated from the dose-volume histogram.

Results

HT provided better uniformity for the planning-target volume dose coverage than both IMRT techniques. The noncoplanar IMRT technique reduces the V10 to normal liver with a statistically significant level as compared to HT. The constraints for the liver in the V30 for coplanar IMRT vs. noncoplanar IMRT vs. HT could be reconsidered as 21% vs. 17% vs. 17%, respectively. When delivering 50 Gy and 60-66 Gy to the tumor bed, the constraints of mean dose to the normal liver could be less than 20 Gy and 25 Gy, respectively.

Conclusion

Noncoplanar IMRT and HT are potential techniques of radiation therapy for HCC patients with PVT. Constraints for the liver in IMRT and HT could be stricter than for 3DCRT.

Management of advanced hepatocellular carcinoma

Many patients are diagnosed with hepatocellular carcinoma (HCC) at an advanced or terminal stage. Due to hepatic decompensation, they have missed the best opportunity for treatment. Of all HCC staging systems, the Barcelona Clinic Liver Cancer (BCLC) staging classification is the only one that can satisfy the aspects of tumor progression, liver function and performance scale. Patients at each stage of BCLC are provided with different therapies. Interventional therapies for advanced HCC include transcatheter arterial chemoembolization (TACE), transcatheter arterial embolization (TAE) and hepatic arterial infusion chemotherapy (HIAC). HIAC may be a choice for patients with poor liver function and portal vein thrombosis (PVT). While systematic therapy for advanced HCC is not recommended and there are still disputes over the efficacy of biotherapies, molecular targeted therapy may become a first-line treatment for advanced HCC.

Stereotactic body radiotherapy for patients with unresectable primary hepatocellular carcinoma: dose-volumetric parameters predicting the hepatic complication

PURPOSE

To identify the parameters that predict hepatic toxicity and deterioration of hepatic function.

MATERIALS AND METHODS

A total of 47 patients with small unresectable primary hepatocellular carcinoma received hypofractionated stereotactic body radiotherapy (SBRT) using the CyberKnife. Of those, 36 patients received no other local treatments that could influence hepatic toxicity at least for 3 months after the completion of SBRT. The gross tumor volume (GTV) was 18.3 ± 15.9 cm(3) (range, 3.0-81.3 cm(3)), and the total dose administered was 30-39 Gy (median, 36 Gy). To assess the deterioration of hepatic function, we evaluated the presence or absence of the progression of Child-Pugh class (CP class). To identify the parameters of predicting the radiation-induced hepatic toxicity and deterioration of the hepatic function, several clinical and dose-volumetric parameters were evaluated.

RESULTS

Of 36 patients, 12 (33%) developed Grade 2 or higher hepatic toxicity and 4 (11%) developed progression of CP class. The multivariate analysis showed that the only significant parameter associated with the progression of CP class was the total liver volume receiving a dose less than 18 Gy (<18 Gy).

CONCLUSIONS

The progression of CP class after SBRT limits other additional local treatments and also reflects the deterioration of hepatic function. Therefore, it would be important to note that the presence or absence of the progression of CP class is a dose-limiting factor. The total liver volume receiving <18 Gy should be greater than 800 cm(3) to reduce the risk of the deterioration of hepatic function.