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

Establishment of a prognosis-related predictive model for hepatocellular carcinoma patients with macrovascular invasion treated with transcatheter arterial chemoembolization combined with intensity modulated radiotherapy

Background

So far, there are still few studies on the prognostic factors of hepatocellular carcinoma (HCC) patients with macrovascular invasion (MVI) treated with transcatheter arterial chemoembolization (TACE) combined with intensity modulated radiotherapy (IMRT), and no relevant model has been established to predict the prognosis of such patients. Thus, the purpose of this study was to determine the prognostic factors of HCC patients with MVI after treatment with TACE combined with IMRT, and to establish a nomogram model for forecasting 1-, 3-, 5-year overall survival (OS) of the patients.

Methods

HCC patients with MVI who were diagnosed and treated at Department of Gastroenterology, 3201 Hospital between January 2010 and December 2020 were enrolled in this study according to the inclusion and exclusion criteria. The risk factors linked to patient OS were determined by performing Cox regression analysis. The nomogram for predicting 1-, 3-, 5-year OS in HCC patients with MVI was stablished and validated based on the results of the Cox regression analysis.

Results

In total, 118 patients were included in the current study. The medium follow-up time was 46 months (range, 29-71 months). Univariate Cox regression analysis revealed that tumor diameter, treatment frequency of TACE, IMRT dose, Child-Pugh grade, liver cirrhosis and alpha fetoprotein (AFP) level were significantly related to the OS of the patients. Further multivariate Cox regression analysis showed that treatment frequency of TACE and Child-Pugh grade, liver cirrhosis and AFP level were the independent prognostic factors of the OS in patients who were treated with TACE combined with IMRT. The nomogram we constructed using the above independent risk factors exhibited good ability for predicting 1-, 3-, 5-year OS of the patients. The concordance-index of the nomogram was 0.727, indicating the nomogram had a good discrimination.

Conclusions

Treatment frequency of TACE and Child-Pugh grade, liver cirrhosis and AFP level were independent predictors of OS in HCC patients with MVI after TACE combined with IMRT treatment. The nomogram that we developed using these predictors provided a convenient tool to predict the survival probability in HCC patients with MVI.

Radiation and Immune Checkpoint Inhibitors: Combination Therapy for Treatment of Hepatocellular Carcinoma

The liver tumor immune microenvironment has been thought to possess a critical role in the development and progression of hepatocellular carcinoma (HCC). Despite the approval of immune checkpoint inhibitors (ICIs), such as programmed cell death receptor 1 (PD-1)/programmed cell death ligand 1 (PD-L1) and cytotoxic T lymphocyte associated protein 4 (CTLA-4) inhibitors, for several types of cancers, including HCC, liver metastases have shown evidence of resistance or poor response to immunotherapies. Radiation therapy (RT) has displayed evidence of immunosuppressive effects through the upregulation of immune checkpoint molecules post-treatment. However, it was revealed that the limitations of ICIs can be overcome through the use of RT, as it can reshape the liver immune microenvironment. Moreover, ICIs are able to overcome the RT-induced inhibitory signals, effectively restoring anti-tumor activity. Owing to the synergetic effect believed to arise from the combination of ICIs with RT, several clinical trials are currently ongoing to assess the efficacy and safety of this treatment for patients with HCC.

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.

Non-Surgical Locoregional Therapies Alone or in Combination with Systemic Therapy in Patients with Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver cancer, representing the third-leading cause of cancer-related deaths worldwide. Curative intent treatment options for patients with HCC include liver transplantation, resection and ablation of small lesions. Other potentially curative therapies include cryoablation, microwave ablation and percutaneous alcohol injection. For locally advanced disease, different arterially directed therapies including transarterial chemoembolization and selective internal radiation therapy, plus external beam radiation including three-dimensional conformal radiation therapy, intensity-modulated radiation therapy, stereotactic body radiation therapy and proton beam therapy, are available or studied. Systemic therapies based on checkpoint inhibitors and tyrosine kinase inhibitors are available for the management of metastatic HCC and sometimes for locally advanced disease. Combinations of locoregional therapies with systemic drugs are currently the subject of several clinical trials.

The α-RECIST (RECIST 1.1 Combined With Alpha Fetoprotein): A Novel Tool for Identifying Tumor Response of Conversion-Radiotherapy for Unresectable Hepatocellular Carcinoma Before Hepatectomy

Purpose

To develop a novel criterion based on the response evaluation criteria in solid tumors (RECIST) 1.1 and alpha fetoprotein (AFP) and evaluate its performance in tumor response for patients with unresectable hepatocellular carcinoma (uHCC) receiving conversion-radiotherapy before hepatectomy.

Method

From June 2012 to December 2020, a total of 39 patients with uHCC, who received intensity-modulated radiotherapy (IMRT) before hepatectomy, were retrospectively included in this study. Pre- and post-treatment contrast-enhanced magnetic resonance imaging (CE-MRI) scans were performed in all patients. Eight modified criteria were developed with the combination of RECIST 1.1, modified RECIST (mRECIST), and the percentage change of AFP, baseline AFP. The endpoint events were recurrence-free survival (RFS).

Results

The median RFS and OS was 26.5 (IQR, 15.7-43.1), 38.8 (IQR, 18.4-53.6) months. An optimal revised evaluation criterion named α-RECIST (alpha fetoprotein-RECIST 1.1) was developed by combining the RECIST 1.1 with the AFPΔ (cut-off value, 76%). Patients defined as responders by α-RECIST showed significantly better RFS and OS than those defined as non-responders (p = 0.035, 0.048). The other criteria (RECIST 1.1, mRECIST, αΔ-mRECIST, α&Δ-RECIST, α&Δ-mRECIST, αBL-RECIST, αBL-mRECIST, α&BL-RECIST, α&BL-mRECIST) all failed to identify responders from non-responders (p = 0.405, 0.201, 0.773, 0.424, 0.266, 0.060, 0.721, 0.644, 0.910, respectively) when correlated with RFS. Responders according to α-RECIST showed significant better RFS compared to non-responders [HR, 0.31 (95% CI: 0.10, 0.98); p=0.046], but no statistical significance was observed in terms of OS [HR, 0.33 (95% CI: 0.11, 1.05); p = 0.06].

Conclusions

Patients identified as responders by α-RECIST provided significant better RFS. The α-RECIST criteria might be a promising tool for identifying tumor response of conversion-radiotherapy for unresectable hepatocellular carcinoma before hepatectomy.

Recent update on comprehensive therapy for advanced hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in the world. The treatment methods for HCC are diverse, mainly including surgical resection, ablation, and liver transplantation. The curative effect can be achieved only for early stage HCC, and it is easy to recur and metastasize after surgery, with a 5-year recurrence rate as high as 70%. Most patients with HCC are in the middle and advanced stage at the time of diagnosis and lose the chance of surgical resection. In recent years, with the in-depth study of the pathogenesis of HCC and the progress of medical science and technology, the systemic treatment of advanced HCC has made a breakthrough. At present, multidisciplinary comprehensive treatment including targeted therapy and immunotherapy has become an effective strategy and inevitable trend for the treatment of advanced HCC. Combined therapy has greatly improved the prognosis of HCC patients and opened up a new milestone in the treatment of this malignancy. In this article, we focus on the treatment progress of advanced HCC to further guide clinical practice.

The effects of several postoperative adjuvant therapies for hepatocellular carcinoma patients with microvascular invasion after curative resection: a systematic review and meta-analysis

Background

For patients with hepatocellular carcinoma (HCC) with microvascular invasion (MVI) after curative resection, the effects of various postoperative adjuvant therapies are not summarized in detail, and the comparison between the effects of various adjuvant therapies is still unclear. Thus, we collected existing studies on postoperative adjuvant therapies for patients with HCC with MVI after curative resection and analyzed the effects of various adjuvant therapies.

Method

We collected all studies on postoperative adjuvant therapy for patients with HCC with MVI after curative resection from PubMed, EMBASE, Cochrane Library and SinoMed ending on May 1, 2019. Overall survival (OS) and disease-free/recurrence-free survival (RFS) between each group were compared in these studies by calculating the pooled hazard ratio (HR) and 95% confidence interval (CI). All statistical analyses were assessed by two authors independently.

Result

A total of 13 studies were included in this study, including 824 postoperative adjuvant transarterial chemoembolization (pa-TACE) patients, 90 postoperative radiotherapy patients, 57 radiofrequency ablation (RFA)/re-resection patients, 16 sorafenib patients and 886 postoperative conservative treatment patients. The results showed that pa-TACE significantly improved OS and RFS compared with postoperative conservative treatment in patients with HCC with MVI after curative resection (HR: 0.64, 95% CI: 0.55–0.74, p < 0.001; HR: 0.70, 95% CI: 0.62–0.78, p < 0.001, respectively). There was no significant difference in OS between pa-TACE and radiotherapy in patients with HCC with MVI (HR: 1.75, 95% CI: 0.92–3.32, p = 0.087). RFS in patients with HCC with MVI after pa-TACE was worse than that after postoperative adjuvant radiotherapy (HR: 2.29, 95% CI: 1.43–3.65, p < 0.001). The prognosis of pa-TACE and RFA/re-resection in patients with MVI with recurrent HCC had no significant differences (HR: 0.65, 95% CI: 0.09–4.89, p = 0.671). Adjuvant treatments significantly improved the OS and RFS of patients compared with the postoperative conservative group (HR: 0.580, 95% CI: 0.480–0.710, p < 0.001; HR: 0.630, 95% CI: 0.540–0.740, p < 0.001, respectively).

Conclusion

Compared with postoperative conservative treatment, pa-TACE, postoperative radiotherapy and sorafenib can improve the prognosis of patients with hepatocellular carcinoma with microvascular invasion after curative resection. Postoperative radiotherapy can reduce the recurrence of patients with HCC with MVI after curative resection compared with pa-TACE.

Stereotactic Body Radiotherapy Based on 99mTc-GSA SPECT Image-guided Inverse Planning for Hepatocellular Carcinoma

BACKGROUND/AIM

A recent planning study suggested that ^99mTc-labelled diethylene triamine pentaacetate-galactosyl human serum albumin (^99mTc-GSA) single-photon emission computed tomography (SPECT) image-guided inverse planning (IGIP) shows dosimetric superiority to conventional planning in sparing liver function. Here, we report the first clinical translation of ^99mTc-GSA SPECT IGIP for stereotactic body radiotherapy (SBRT) in a patient with hepatocellular carcinoma (HCC).

CASE REPORT

A 60-year-old male developed obstructive jaundice caused by recurrent HCC in segment 1 after hepatic resection. He underwent repeated radiotherapy (RT) consisting of 45 Gy in 15 fractions 8 years ago and 30 Gy in 5 fractions 2 years ago. We performed SBRT consisting of 40 Gy in 8 fractions using ^99mTc-GSA SPECT-IGIP. We confirmed the dosimetric superiority of functional IGIP to conventional planning. He achieved complete response as assessed using the target volume. The patient has remained alive without recurrence for 18 months. He did not experience radiation-induced liver disease.

CONCLUSION

Recurrent HCC was successfully and safely salvaged via re-irradiation with SBRT using ^99mTc-GSA SPECT-IGIP.

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.

Proton versus photon radiotherapy for primary hepatocellular carcinoma: a propensity-matched analysis

Background

Proton radiotherapy has a dosimetric advantage over photon radiotherapy. Many retrospective studies have shown promising results with proton radiotherapy in treating hepatocellular carcinoma (HCC). However, clinical evidence demonstrating the benefit of protons over photons is still limited. We therefore compared the clinical outcomes of the two modalities using medical research databases from our medical foundation.

Methods

We conducted a propensity score-matched cohort study based on our multi-institution medical organization research database. From January 2007 to January 2018, a total of 413 patients (photon: 349; proton: 64) who were diagnosed with HCC and primarily treated with radiotherapy with curative intent were enrolled. Overall survival (OS) and radiation-induced liver disease (RILD) were assessed. Stratified analysis was also performed to evaluate the heterogeneous effects of the two arms.

Results

A total of 110 patients (photon: 55; proton: 55) were analyzed in the propensity-matched series. The matched groups were balanced for baseline tumor risk factors. Cox regression analysis revealed a significant survival benefit in the proton group (p = 0.032, HR 0.56, 95% CI 0.33–0.96). The median overall survival in the proton group was not reached and that in the photon group was 17.4 months. The biological equivalent dose of radiotherapy was significantly higher in the proton group than in the photon group (median, 96.56 Gray [relative biological effectiveness] vs. 62.5 Gray, p < 0.001). The risk of RILD was significantly lower in the proton group (11.8% vs. 36%, p = 0.004).

Conclusions

Proton radiotherapy could deliver a higher radiation dose than photon radiotherapy without increasing the risk of RILD and result in a better overall survival rate for those diagnosed with HCC and treated with radiotherapy with curative intent.

Comparing efficacy of high-dose rate brachytherapy versus helical tomotherapy in the treatment of cervical cancer

Objective

Boost radiation using brachytherapy (BT) is a standard treatment for local disease control in concomitant chemoradiation therapy (CCRT) for advanced cervical cancer. However, it is associated with gastrointestinal and genitourinary complications. Hence, this study investigates the feasibility of helical tomotherapy (HT) as an alternative to BT.

Methods

Medical records of patients who underwent CCRT between 2000 and 2017 at a single institution were retrospectively reviewed. Patients with stage IIB–IVA cancers were selected based on the 2009 criteria of The International Federation of Gynaecology and Obstetrics. External beam radiation combined with chemotherapy was followed by either BT or HT. The propensity score matching of both groups was calculated using logistic regression analysis. Disease outcomes and treatment-related adverse events were compared between the 2 groups.

Results

The matched population included 70 BT patients and 35 HT patients. The 5-year progression-free survival rates for BT and HT were 72.6% and 72.5%, respectively (p=0.721). There was no difference in the overall survival rate between the two groups (p=0.203). The presence of acute and chronic gastrointestinal complications was also similar between the groups (p=0.460 and p=0.563, respectively). The chronic genitourinary toxicities were also comparable (p=0.105).

Conclusions

HT boost treatment showed comparable disease outcomes with those observed with conventional BT in patients with advanced cervical cancer. HT could be a complementary boost protocol as a single modality or hybrid with BT in selected patients. Further studies with longer follow-up periods are warranted to confirm long-term outcomes.

Novel Radiotherapy Technologies in the Treatment of Gastrointestinal Malignancies

Over the past 2 decades, major technical advances in radiation therapy planning and delivery have made it possible to deliver higher doses to select high-risk volumes. This has helped to expand the role of radiation therapy in the treatment of gastrointestinal malignancies. Whereas dose escalation was previously limited by the radiosensitivity of normal tissues within and adjacent to the gastrointestinal tract, advances in target delineation, patient immobilization, treatment planning, and image-guided treatment delivery have greatly improved the therapeutic ratio. More conformal radiation modalities can offer further dose optimization to target volumes while sparing normal tissue from toxicity.

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.

Impact of 99mTc-GSA SPECT Image-Guided Inverse Planning on Dose-Function Histogram Parameters for Stereotactic Body Radiation Therapy Planning for Patients With Hepatocellular Carcinoma: A Dosimetric Comparison Study

Purpose:

To evaluate the impact of ^99mTc-labeled diethylene triamine pentaacetate-galactosyl human serum albumin (^99mTc-GSA) single-photon emission computed tomography (SPECT) image-guided inverse planning on the dose–function histogram (DFH) parameters for stereotactic body radiation therapy planning in patients with hepatocellular carcinoma (HCC).

Methods:

Eleven patients were enrolled in this study. The functional liver structure (FLS) was derived from SPECT thresholds of 60% to 80% of the maximum pixel value. Two treatment plans optimized without FLS (plan C) and with FLS (plan F) were designed for 50 Gy to the planning target volume (PTV). The DFH parameters were calculated as follows: Fx = (sum of the counts within the liver volume receiving a dose >x Gy/sum of the counts within the whole liver volume) × 100. Other parameters for the PTV included D₉₅, mean dose, conformity index (CI), and homogeneity index (HI).

Results:

Compared with plan C, plan F significantly reduced DFH parameters of F₅ to F₄₀ (P < .05). There were no significant differences in the parameters of the PTV of D₉₅, mean dose, CI, and HI and organs at risks (stomach, duodenum, spinal cord, and kidneys) between plans C and F.

Conclusion:

DFH analyses revealed that ^99mTc-GSA SPECT image-guided inverse planning provided dosimetric benefits related to sparing of liver function and may reduce hepatic toxicities.

Synuclein gamma expression enhances radiation resistance of breast cancer cells

Resistance to therapy is a major obstacle for the effective treatment of cancer. Expression of synuclein-gamma (SNCG) has been associated with poor prognosis and resistance to therapy. While reports on SNCG overexpression contributing to chemoresistance exist, limited information is available on the relationship between SNCG and radioresistance of cancer cells. Here we investigated the role of SNCG in radiation resistance in breast cancer cells. siRNA mediated knockdown of SNCG (siSNCG) markedly reduced SNCG protein level compared to scrambled siRNA (siScr) treatment. Furthermore, siSNCG treatment sensitized Estrogen Receptor-positive breast cancer cells (MCF7 and T47D) to ionizing radiation at 4 to 12 Gy as evidenced by the significant increase of apoptotic or senescent cells and reduction in clonogenic cell survival in siSNCG treated cells compared to siScr treated cells. On the other hand, we established an in vitro model of SNCG ectopic expression by using a triple-negative breast cancer cell line (SUM159PT) to further investigate the radioprotective effect of SNCG. We showed that ectopic expression of SNCG significantly decreased apoptosis of SUM159PT cells and enhanced clonogenic cell survival after radiation treatment. At the molecular level, after irradiation, the p53 pathway was less activated when SNCG was present. Conversely, p21^Waf1/Cip1 expression was upregulated in SNCG-expressing cells. When p21 was down-regulated by siRNA, radiosensitivity of SNCG-expressing SUM159PT cells was dramatically increased. This suggested a possible connection between p21 and SNCG in radioresistance in these cells. In conclusion, our data provide for the first time experimental evidence for the role of SNCG in the radioresistance of breast cancer cells.

Long non-coding RNA ROR promotes radioresistance in hepatocelluar carcinoma cells by acting as a ceRNA for microRNA-145 to regulate RAD18 expression

Radiotherapy plays a limited role in the treatment of hepatocellular carcinoma (HCC) due to the development of resistance. Therefore, further investigation of underlying mechanisms involved in HCC radioresistance is warranted. Increasing evidence shows that long non-coding RNAs (linc-RNAs) are involved in the pathology of various tumors, including HCC. Previously, we have shown that long noncoding RNA regulator of reprogramming (linc-ROR) promotes HCC metastasis via induction of epithelial-mesenchymal transition (EMT). However, the roles of linc-ROR in HCC radioresistance and its possible mechanisms are unclear. Here, we established two radioresistant HCC cell lines (HepG2-R and SMMC-7721-R) and found that linc-ROR was significantly upregulated in radioresistant HCC cells. Knockdown of linc-ROR reduces in vitro and in vivo radiosensitivity of parental HCC cells by reducing DNA repair capacity, while ectopic expression of linc-ROR enhances radiosensitivity of radioresistant HCC cells. Further mechanistic investigations revealed that lincRNA-ROR exerted its biological effects by acting as a competing endogenous RNA (ceRNA) for miR-145 to regulate RAD18 expression, thereby promoting DNA repair. Collectively, our findings demonstrate that linc-ROR promotes HCC radioresistance and targeting it will be a promising strategy for enhancing the efficacy of radiotherapies in HCC.