Treatment outcomes of helical intensity-modulated radiotherapy for unresectable hepatocellular carcinoma

The Current Evidence of Intensity-Modulated Radiotherapy for Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis

Intensity-modulated radiotherapy (IMRT), an advanced RT technique, is a considerable treatment option for hepatocellular carcinoma (HCC). However, the distinguishing features of IMRT for HCC have not yet been clearly defined. A systematic review was performed according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The PubMed/MedLine, Embase, Cochrane Library, Web of Science, and KoreaMed were used to screen eligible studies focusing on treatment outcomes after IMRT for HCC until 18 April 2023. A total of 1755 HCC patients receiving IMRT among 29 studies from 2009 to 2023 were selected for the meta-analysis. The median proportion of Barcelona Clinic Liver Cancer stage C was 100% (range: 38-100%). Nineteen studies used combined treatment. Pooled rates of response and 1-year local control were 58% (95% confidence interval [CI], 50-65%) and 84% (95% CI, 70-94%), respectively. The median overall survival (OS) was 13 months (range: 5-45 months), and pooled 1- and 3-year OS rates were 59% (95% CI, 52-66%), and 23% (95% CI, 14-33%), respectively. Pooled rates of classic radiation-induced liver disease (RILD), nonclassic RILD, and hepatic toxicity ≥ grade 3 were 2%, 4%, and 4%, respectively. Although most patients had advanced-stage HCC and combined treatment was commonly used, IMRT for HCC showed similar survival to existing RT modalities and relatively low severe toxicity.

Therapeutic options in hepatocellular carcinoma: a comprehensive review

Hepatocellular carcinoma (HCC) is a chronic liver disease that is highly fatal if not detected and treated early. The incidence and death rate of HCC have been increasing in recent decades despite the measures taken for preventive screening and effective diagnostic and treatment strategies. The pathophysiology of HCC is multifactorial and highly complex owing to its molecular and immune heterogeneity, and thus the gap in knowledge still precludes making choices between viable therapeutic options and also the development of effective regimens. The treatment of HCC demands multidisciplinary approaches and primarily depends on tumor stage, hepatic functional reserve, and response to treatment by patients. Although curative treatments are limited but critical in the early stages of cancer, there are numerous palliative treatments available for patients with intermediate and advanced-stage HCC. In recent times, the use of combination therapy has succeeded over the use of monotherapy in the treatment of HCC by achieving effective tumor suppression, increasing survival rate, decreasing toxicity, and also aiding in overcoming drug resistance. This work focuses on reviewing the current and emerging treatment strategies for HCC.

Role of External Beam Radiotherapy in Hepatocellular Carcinoma

External beam radiotherapy (EBRT) has improved efficacy and safety with advancements in technology and techniques. EBRT plays an important role in management of hepatocellular carcinoma (HCC). In resectable cases, EBRT serves as a bridge to transplantation or improves local control through adjuvant radiotherapy. In unresectable patients, EBRT offers high local control rates. In metastatic settings, EBRT provides effective palliation. This review presents an overview of radiotherapy treatment modalities used for HCC, current treatment guidelines for the role of EBRT in HCC, clinical outcomes between various EBRT approaches and other locoregional treatments for HCC, and the future role of EBRT for HCC.

Role of Radiotherapy in the Treatment of Hepatocellular Carcinoma

The role of radiotherapy in the treatment of hepatocellular carcinoma (HCC) has evolved over the past few decades with the advancement of technology and improved imaging. Radiotherapy can offer high local control rates in unresectable HCC, including cases with major vascular involvement, and can provide a modality to help bridge patients to potentially curative resection or transplantation. In metastatic cases, radiotherapy can provide good palliation. This review focuses on the common radiotherapy treatment modalities used for HCC, provides outcome comparisons of these radiotherapy techniques to outcomes with other treatment modalities for HCC, and highlights the discrepancy of the role of radiotherapy in HCC amongst the current available treatment guidelines.

Rethinking the Role of Radiation Therapy in the Treatment of Unresectable Hepatocellular Carcinoma: A Data Driven Treatment Algorithm for Optimizing Outcomes

Hepatocellular carcinoma (HCC) is the second most common cause of cancer death worldwide, with a majority of HCC patients not suitable for curative therapies. Approximately 70% of initially diagnosed patients cannot undergo surgical resection or transplantation due to locally advanced disease, poor liver function/underlying cirrhosis, or additional comorbidities. Local therapeutic options for patients with unresectable HCC, who are not suitable for thermal ablation, include transarterial embolization (bland, chemoembolization, radioembolization) and/or external beam radiation therapy (EBRT). Regarding EBRT specifically, technological advancements provide a means for safe and effective radiotherapy delivery in a wide spectrum of HCC patients. In multiple prospective studies, EBRT delivery in a variety of different fractionation schemes or in combination with transcatheter arterial chemoembolization (TACE) demonstrate improved outcomes, particularly with combination therapy. The Barcelona Clinic Liver Cancer classification provides a framework for treatment selection; however, given the growing complexity of treatment strategies, this classification system tends to simplify decision-making. In this review, we discuss the current literature regarding unresectable HCC and propose a modified treatment algorithm that emphasizes the role of radiation therapy for Child-Pugh score A or B patients with ≤3 nodules measuring >3 cm, multinodular disease or portal venous thrombosis.

Intensity-modulated radiotherapy for hepatocellular carcinoma: dosimetric and clinical results

Since the introduction of 3-dimensional conformal radiotherapy (3DCRT), new radiotherapy techniques have expanded the indication of radiotherapy for the treatment of hepatocellular carcinoma (HCC), from the hitherto palliative to a now curative-intent purpose. Intensity-modulated radiotherapy (IMRT), currently the most advanced radiotherapy technique, is considered an attractive option for the treatment of HCC, and is more widely applied because it can deliver a higher dose to the tumor than 3DCRT while sparing surrounding normal organs. However, the advantages and potential disadvantages of IMRT for treating HCC have not been fully established. This article deals with three different IMRT techniques, including static IMRT and volumetric modulated arc therapy using conventional multileaf collimator (MLC) mounted linear accelerators, and helical IMRT using binary MLC mounted helical tomotherapy machine. We review dosimetric and clinical studies for these IMRT techniques for the treatment of HCC.

External radiation or ablation for solitary hepatocellular carcinoma: A survival analysis of the SEER database

BACKGROUND AND OBJECTIVES

Hepatocellular carcinoma (HCC) patients are often not candidates for resection. This study hypothesized that external beam radiation (XRT) could be equally effective compared to ablation therapy (AT) for selected HCC patients.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was used to identify HCC patients (2004-2012) undergoing XRT or AT for solitary HCC lesions. Propensity score modeling was utilized to adjust for baseline characteristics.

RESULTS

Propensity matching identified 784 patients: 157 (20%) XRT and 627 (80%) AT. Median OS for XRT and AT was 22, and 32 months (P < 0.001), respectively. AT demonstrated improved OS for tumors 3-5 cm (30 vs 16 m, P < 0.001) and >5 cm (25 vs 9 m, P < 0.001). Similar survival was found in patients with tumor size <3 cm (37 vs 47 m P = 0.508). Following multivariate analyses, XRT was associated with an increased hazard ratio (HR = 1.64, P < 0.001). Elevated AFP at diagnosis (HR = 1.54, P = 0.001) and tumor size >3 were identified as negative predictors of survival.

CONCLUSIONS

Similar survival for solitary HCC lesions <3 cm exists between XRT and AT. However, AT demonstrates improved survival rates compared to XRT for lesions >3 cm. This 3 cm reference point may serve as a valuable metric to guide treatment decisions and future investigations.

Efficacy and Safety of Intensity-Modulated Radiotherapy Following Transarterial Chemoembolization in Patients With Unresectable Hepatocellular Carcinoma

Three-dimensional conformal radiotherapy in combination with transarterial chemoembolization (TACE) has been beneficial in patients with unresectable hepatocellular carcinoma (HCC). There have been few clinical reports on the use of intensity-modulated radiotherapy (IMRT) in combination with TACE for these patients. The purpose of this study was to assess the efficacy and toxicity of IMRT following TACE in unresectable HCC.The medical records of consecutive patients with unresectable HCC, who underwent IMRT following TACE from January 2009 to June 2014, were retrospectively reviewed in order to assess the overall survival (OS), progression-free survival (PFS), tumor response, and treatment-associated toxicity.A total of 64 lesions in 54 patients were included in the analysis. IMRT was delivered at a median dose of 50 Gy (range 44-70 Gy) at 1.8 to 2.0 Gy per fraction. The overall response rate was achieved in 64.8% of patients with complete response in 20.4% of patients at 3 months after completion of IMRT. The median OS was 20.2 months (95% CI = 8.6-31.9), and the actuarial 1-, 2-, and 3-year OS rates were 84.6%, 49.7%, and 36.7%, respectively. The median PFS was 10.5 months (95% CI = 7.3-13.7) and the 1-, 2-, and 3-year PFS rates were 44.2%, 23.4%, and 14.6%, respectively. The responders had a significantly higher OS rate than the nonresponders (3-year OS 48.0% vs 14.4%, P = 0.001). During and the first month following IMRT, 10 (18.5%) patients developed grade 3 hematological toxicity, and 3 (5.6%) developed grade 3 hepatic toxicity. No patient experienced grade 4 or 5 toxicity. Radiation-induced liver disease was not observed.Our findings suggest that IMRT following TACE could be a favorable treatment option for both its safety profile and clinical benefit in patients with unresectable HCC.

Risk of radiation-induced pneumonitis after helical and static-port tomotherapy in lung cancer patients and experimental rats

BACKGROUND

Radiotherapy (RT) is one of the major non-operative treatment modalities for treating lung cancer. Tomotherapy is an advanced type of intensity-modulated radiotherapy (IMRT) in which radiation may be delivered in a helical fashion. However, unexpected pneumonitis may occur in patients treated with tomotherapy, especially in combination with chemotherapy, as a result of extensive low-dose radiation of large lung volumes. The aim of our study was to investigate the risk of radiation-induced pneumonitis after helical-mode and static-mode tomotherapy in patients with lung cancer and in an animal model.

METHOD

A total of 63 patients with primary lung cancer who were treated with static or helical tomotherapy with or without concurrent chemoradiotherapy (CCRT) were analyzed. Additionally, rats with radiation-induced pulmonary toxicity, which was induced by the application of helical or static tomography with or without CCRT, were evaluated.

RESULTS

Helical-mode tomotherapy resulted in a significantly higher rate of late radiation pneumonitis in lung cancer patients than static-mode tomotherapy when evaluated by the Radiation Therapy Oncology Group (RTOG) and National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) scoring system. In the animal model, helical tomotherapy alone induced significantly higher expression of interleukin (IL)-1α, IL-1β, IL-6, and transforming growth factor (TGF)-β in lung specimens, especially on the untreated side, compared to static tomotherapy alone. Additionally, rats treated with helical tomotherapy and CCRT demonstrated significantly higher expression of inflammatory cytokines compared to those treated with static tomotherapy and CCRT.

CONCLUSION

Rat models treated with tomotherapy with or without CCRT could present similar patterns of pulmonary toxicity to those shown in lung cancer patients. The models can be used in further investigations of radiation induced pulmonary toxicity.

Feasibility and efficacy of helical tomotherapy in cirrhotic patients with unresectable hepatocellular carcinoma

Background

This study is to evaluate the toxicity and outcomes of helical tomotherapy (HT) in patients treated for unresectable hepatocellular carcinoma (HCC).

Methods

From March 2008 to September 2010, 38 patients with unresectable HCC were treated with HT. The median patient age was 67 years (range, 45–85). The median follow-up period was 17.2 months (range, 7–46). All patients had liver cirrhosis. Median radiation dose was 54 Gy (range, 46–71.8) delivered in 1.8 to 2.4-Gy fractions. The planning target volumes were 241.2 ± 153.1 cm³ (range, 45.8–722.4). Treatment responses were assessed in 3–6 months after HT.

Results

There was a complete response in 2 patients (5.2 %), partial response in 18 patients (47.4 %), stable disease in 13 patients (34.2 %), and progressive disease in 5 patients (13.2 %). The median overall survival was 12.6 months, and 1- and 2-year overall survival rates were 56.2 and 31.7 %, respectively. Eastern Cooperative Oncology Group (ECOG score, p = 0.008), Child-Pugh classification (p = 0.012), albumin (p = 0.046), and hemoglobin (p = 0.028) were significant parameters that predicted primary tumor response to radiotherapy in multivariate analysis. ECOG score (p = 0.012), Child-Pugh class (p = 0.026), and response to radiotherapy (p = 0.016) were independent prognostic factors for overall survival in multivariate analysis. Responders had better overall survival than non-responders (23.6 vs. 5.8 months, p < 0.001). The 1- and 2-year overall survival rates for responders were 68.3 and 57 %, respectively, while for non-responders, they were 0 %. The 1- and 2-year local control rates were 88.2 and 82.3 %, respectively. Five patients (13.2 %) had grade 3 or greater liver toxicity, and one patient (2.6 %) had a grade 3 gastric ulcer. No treatment-related liver failure or death was documented in this study.

Conclusions

Radiotherapy using HT seems to be a safe and effective treatment option for unresectable HCC patients. This study indicates that HT is a feasible treatment even in patients without good performance status and hepatic function reservation.

Multimodality treatment with radiotherapy for huge hepatocellular carcinoma

BACKGROUND

For huge hepatocellular carcinoma (HCC), therapeutic decisions have varied from local therapy to systemic therapy, with radiotherapy (RT) playing only a palliative role. In this study, we investigated whether multimodality treatment involving RT could be effective in huge HCC.

RESULTS

This study was performed in 116 patients with HCC >10 cm. The number of patients in stage II, III and IV was 12, 54 and 50, respectively. RT was given as a combined modality in most patients. The median dose was 45 Gy, with 1.8 Gy per fraction. The median overall survival (OS) and progression-free survival (PFS) were 14.8 and 6.5 months, respectively. The median infield PFS was not reached. Infield failure, outfield intrahepatic and extrahepatic failure were observed in 8.6, 18.1, and 12.1% of patients, respectively. For OS and PFS, number of tumors, initial alpha-fetoprotein (AFP) level, treatment response, percent AFP decrement, and hepatic resection were significant prognostic factors. Tumor characteristics and treatment response were significantly different between long-term survivors and the other patients.

CONCLUSION

Although huge HCC presents an aggressive clinical course, multimodality approaches involving RT can offer an opportunity for prolonged survival.

Optimal follow-up duration for evaluating objective response to radiotherapy in patients with hepatocellular carcinoma: a retrospective study

The time to complete or partial (objective) response to radiotherapy in patients with hepatocellular carcinoma (HCC) is variable; thus, the reported frequency of these responses depends on the length of follow-up. However, the optimum follow-up duration is unknown. We sought to determine the optimal follow-up duration by analyzing the medical records of 25 patients with 39 HCC lesions who received definitive helical tomotherapy at a daily dose of 2 to 4 Gy at 5 fractions per week, for a total dose of 40 to 60 Gy, between January 2008 and January 2013. We determined the time to objective treatment response and local recurrence after radiotherapy and assessed several predictors of delayed treatment response. The median follow-up duration was 15.2 months (range, 7.8 to 52.1 months). Among all 39 lesions, objective responses were observed for 36 (92.3%). The median time to objective response was 3.9 months (range, 1.5 to 9.8 months). The objective response rates increased over time from 15.4% at 3 months to 71.8% at 6 months and 87.2% at 9 months. Age 60 years old or older and post-radiotherapy α-fetoprotein concentrations higher than pre-radiotherapy concentrations predicted delayed treatment response. The objective response rate continued to increase over 9 months. Therefore, to fully evaluate the treatment response of HCC, we recommend continuous observation for at least 9 months after radiotherapy.

Conventional fractionated helical tomotherapy for patients with small to medium hepatocellular carcinomas without portal vein tumor thrombosis

Background

The purpose of this study was to evaluate clinical outcomes of conventional fractionated helical tomotherapy in patients with small to medium hepatocellular carcinomas (HCCs) without portal vein tumor thrombosis.

Methods

Patients with up to four HCC lesions not treatable by surgery or percutaneous ablative therapies, <10 cm in the longest diameter, and no evidence of major vascular invasion were included. From January 2008 to January 2013, 20 patients with 33 tumors met the eligibility criteria and received definitive or salvage helical tomotherapy. The most commonly prescribed dose fractionation schedule was a total dose of 50 Gy with a daily dose of 2.5 Gy. Treatment response, survival, and radiation-induced toxicities were retrospectively reviewed.

Results

The median follow-up period after radiotherapy for all patients was 24.9 (range 7.8–79.2) months. Objective responses (complete response or partial response) occurred in 30 of 33 lesions (90.9%). Eight (24.2%) lesions showed local recurrence and the actuarial local control rate at 2 years was 69.5%. Intrahepatic recurrence-free survival and overall survival rates at 2 years were 45.7% and 71.1%, respectively. Age, Child–Pugh class, tumor response, local recurrence status, and intrahepatic recurrence status were significantly associated with overall survival on univariate analysis. Among these parameters, only local recurrence status showed marginal statistical significance on multivariate analysis (P=0.068). The overall survival rate at 2 years was 50% for patients who experienced local recurrence, but 87.5% for those who did not. No patient experienced grade 2 or greater general or gastrointestinal toxicity. There were no cases of radiation-induced liver disease.

Conclusion

Conventional fractionated helical tomotherapy for patients with less than four small to medium HCCs without portal vein tumor thrombosis yielded favorable local control and overall survival without severe complications.

Short-term effects of cyberknife combined with TACE for treatment of primary liver cancer

AIM: To evaluate the short-term clinical effects and adverse reactions of cyberknife combined with transarterial chemoembolization (TACE) for the treatment of primary liver cancer.

METHODS: The medical records for 108 patients with primary liver cancer who received cyberknife and TACE between January 2012 and May 2013 were retrospectively reviewed. Patient demographics, tumor characteristics, treatment details and post-treatment complications were recorded for each patient.

RESULTS: There were 96 males and 12 females. Intra-arterial chemoembolization and cyberknife (DT 35-60 Gy/3-6 fraction/3-7 d) were performed successfully, resulting in a substantial reduction or complete disappearance of tumors in nearly all patients, with a total effective rate (CR + PR + SD) of 100%. No major complications were encountered.

CONCLUSION: Cyberknife combined with TACE for the treatment of primary liver cancer is effective with mild adverse reactions.

Differential regulation of ferritin subunits and iron transport proteins: an effect of targeted hepatic X-irradiation

The current study aimed to investigate radiation-induced regulation of iron proteins including ferritin subunits in rats. Rat livers were selectively irradiated in vivo at 25 Gy. This dose can be used to model radiation effects to the liver without inducing overt radiation-induced liver disease. Sham-irradiated rats served as controls. Isolated hepatocytes were irradiated at 8 Gy. Ferritin light polypeptide (FTL) was detectable in the serum of sham-irradiated rats with an increase after irradiation. Liver irradiation increased hepatic protein expression of both ferritin subunits. A rather early increase (3 h) was observed for hepatic TfR1 and Fpn-1 followed by a decrease at 12 h. The increase in TfR2 persisted over the observed time. Parallel to the elevation of AST levels, a significant increase (24 h) in hepatic iron content was measured. Complete blood count analysis showed a significant decrease in leukocyte number with an early increase in neutrophil granulocytes and a decrease in lymphocytes. In vitro, a significant increase in ferritin subunits at mRNA level was detected after irradiation which was further induced with a combination treatment of irradiation and acute phase cytokine. Irradiation can directly alter the expression of ferritin subunits and this response can be strongly influenced by radiation-induced proinflammatory cytokines. FTL can be used as a serum marker for early phase radiation-induced liver damage.