Adjuvant radiotherapy in central hepatocellular carcinoma after narrow-margin hepatectomy: A 10-year real-world evidence

Locoregional Therapies for Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis

Importance

Several locoregional therapies (LRTs) for nonmetastatic hepatocellular carcinoma (HCC) are available; however, a global comparison of the relative efficacy of each is needed.

Objective

To conduct a systematic review and direct, pairwise meta-analytic comparison of all identified randomized clinical trials evaluating the treatment of nonmetastatic HCC.

Data Sources

A comprehensive search of PubMed and the proceedings of the American Society of Clinical Oncology and American Society for Radiation Oncology annual meetings from January 1, 2010, to November 1, 2023, was performed.

Study Selection

Randomized clinical trials using a form of LRT (surgery with or without adjuvant therapy, radiofrequency ablation [RFA], microwave ablation [MWA], radiotherapy [RT], hepatic arterial infusion chemotherapy [HAIC], transarterial bland embolization [TAE], transarterial chemoembolization [TACE], or transarterial radioembolization [TARE]).

Data Extraction and Synthesis

Study eligibility and data extraction were each reviewed by 2 authors independently. Random-effects meta-analyses were used to compare treatment categories.

Main Outcomes and Measures

Progression-free survival (PFS) was the primary outcome; overall survival (OS) was the secondary outcome.

Results

Forty randomized clinical trials reporting on comparative outcomes of 11 576 total patients with localized HCC treated with LRT were included. The median follow-up was 30.0 (IQR, 18.5-40.8) months. Direct pooled comparisons between treatment classes suggested improved outcomes for surgery combined with adjuvant therapy over surgery alone (PFS: hazard ratio [HR], 0.62 [95% CI, 0.51-0.75]; P < .001; OS: HR, 0.61 [95% CI, 0.48-0.78]; P < .001), surgery over RFA (PFS: HR, 0.74 [95% CI, 0.63-0.87]; P < .001; OS: HR, 0.71 [95% CI, 0.54-0.95]; P = .02), RT over TACE (PFS: HR, 0.35 [95% CI, 0.21-0.60]; P < .001; OS: HR, 0.35 [95% CI, 0.13-0.97]; P = .04), and HAIC over TACE (PFS: HR, 0.57 [95% CI, 0.45-0.72]; P < .001; OS: HR, 0.58 [95% CI, 0.45-0.75]; P < .001). No substantial heterogeneity was noted for any pairwise comparison with the exception of RT-based regimens compared with tyrosine kinase inhibitor therapy.

Conclusions and Relevance

The findings of this systematic review and direct, pairwise meta-analysis suggest that all LRTs are not equivalent for the treatment of localized HCC. The efficacy of LRTs appears hierarchical, with surgery-based management outcomes associated with the best treatment outcomes and embolization-based treatment options associated with the worst treatment outcomes.

Long-term outcome of adjuvant radiotherapy upon postoperative relapse of centrally located hepatocellular carcinoma: a real-world study

Despite that surgical resection is widely regarded as the most effective approach to the treatment of liver cancer, its safety and efficacy upon centrally located hepatocellular carcinoma (HCC) remain unsatisfactory. In consequence, seeking an integrated treatment, like combined with adjuvant radiotherapy, to enhance the prognosis of patients is of critical importance. By recruiting patients undergoing surgical resection for centrally located HCC ranging from June 2015 to 2020, they were divided into liver resection combined with adjuvant radiotherapy (LR + RT) and mere liver resection (LR) groups. The calculation of propensity score and model of Cox proportional hazards regression were utilized. 193 patients were recruited in aggregation, containing 88 ones undergoing LR + RT, while 105 handled with LR. RT was verified to be an independent factor of prognosis for relapse (HR 0.60). In propensity-score analyses, significant association existed between adjuvant radiotherapy and better disease-free survival (DFS) (Matched, HR 0.60; Adjustment of propensity score, HR 0.60; Inverse probability weighting, HR 0.63). The difference of DFS was apparent within two groups (p value = 0.022), and RT significantly down-regulated early relapse (p value < 0.05) in subgroup analysis. The calculation of E-value revealed robustness of unmeasured confounding. The combination of liver surgical resection with RT is safe and effective towards patients with centrally located HCC, which would notably enhance the prognosis and decrease the early relapse of HCC.

The Current and Prospective Adjuvant Therapies for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) stands as the most prevalent form of primary liver cancer and is highly invasive and easily recurs. For HCC, chemotherapy shows limited effect. The gold standard for HCC treatment includes curative surgical resection or liver transplantation. However, the recurrence rate at 5 years after liver resection is estimated at approximately 70% and even at 5 years after liver transplantation, it is 20%. Therefore, improving survival outcomes after curative surgical resection of liver cancer is crucial. This review highlights the importance of identifying risk factors for HCC recurrence following radical surgical resection and adjuvant therapy options that may reduce the recurrence risk and improve overall survival, including local adjuvant therapy (e.g., transcatheter arterial chemoembolization and radiotherapy), adjuvant systemic therapy (e.g., small molecule targeted therapy and immunotherapy), and other adjuvant therapies (e.g., chemotherapy). However, further research is needed to refine the use of these therapies and optimize their effectiveness in preventing HCC recurrence.

Radiotherapy is superior to transarterial chemoembolization as adjuvant therapy after narrow-margin hepatectomy in patients with hepatocellular carcinoma: A single-center prospective randomized study

BACKGROUND

This study was recruited to compare the efficacy and safety of radiotherapy (RT) and transarterial chemoembolization (TACE) as postoperative adjuvant therapy after narrow-margin hepatectomy in hepatocellular carcinoma (HCC) patients.

METHODS

This single-center prospective randomized study was conducted in the Cancer Hospital, Guang Xi Medical University, Nanning. A total of 72 patients who received treatment in this hospital between August 2017 and July 2019 were included and randomly allocated to TACE group (n = 48) and RT group (n = 24). Next, overall survival (OS) and progression-free survival (PFS) rates, recurrence patterns, financial burden, and safety were evaluated.

RESULTS

The difference between the RT and TACE groups was not significant in one-, three-, and five-year OS (87.5%, 79.0%, and 62.5% vs. 93.8%, 75.9%, and 63.4%, respectively, P = 0.071) and PFS rates (79.0%, 54.2%, and 22.6% vs. 75.0%, 47.9%, and 32.6%, respectively, P = 0.071). Compared to the TACE group, the RT group had significantly lower intrahepatic recurrence rate (20.8% vs. 52.1%, P = 0.011), higher extrahepatic recurrence rate (37.5% vs. 14.6%, P = 0.034), and no marginal and diffuse recurrences (0% vs. 16.7%, P < 0.05). The mean overall treatment cost was higher (¥62,550.59 ± 4397.27 vs. ¥40,732.56 ± 9210.54, P < 0.01), the hospital stay (15.1 ± 3.7 vs. 11.8 ± 4.1 days, P < 0.01) was longer, and the overall treatment stay (13.3 ± 5.3 vs. 41.29 ± 12.4 days, P < 0.01) was shorter in the TACE group than in the RT group. Besides, both groups did not exhibit significant differences in the frequency and severity of adverse events.

CONCLUSION

Both adjuvant TACE and RT can better the OS and PFS of patients with HCC. However, RT has a significantly better performance than TACE in terms of improving intrahepatic recurrence rate, treatment cost and hospital stay.

Unraveling the efficacy network: A network meta-analysis of adjuvant external beam radiation therapy methods after hepatectomy

BACKGROUND

Primary liver cancer is a malignant tumor with a high recurrence rate that significantly affects patient prognosis. Postoperative adjuvant external radiation therapy (RT) has been shown to effectively prevent recurrence after liver cancer resection. However, there are multiple RT techniques available, and the differential effects of these techniques in preventing postoperative liver cancer recurrence require further investigation.

AIM

To assess the advantages and disadvantages of various adjuvant external RT methods after liver resection based on overall survival (OS) and disease-free survival (DFS) and to determine the optimal strategy.

METHODS

This study involved network meta-analyses and followed the PRISMA guidelines. The data of qualified studies published before July 10, 2023, were collected from PubMed, Embase, the Web of Science, and the Cochrane Library. We included relevant studies on postoperative external beam RT after liver resection that had OS and DFS as the primary endpoints. The magnitudes of the effects were determined using risk ratios with 95% confidential intervals. The results were analyzed using R software and STATA software.

RESULTS

A total of 12 studies, including 1265 patients with hepatocellular carcinoma (HCC) after liver resection, were included in this study. There was no significant heterogeneity in the direct paired comparisons, and there were no significant differences in the inclusion or exclusion criteria, intervention measures, or outcome indicators, meeting the assumptions of heterogeneity and transitivity. OS analysis revealed that patients who underwent stereotactic body radiotherapy (SBRT) after resection had longer OS than those who underwent intensity modulated radiotherapy (IMRT) or 3-dimensional conformal RT (3D-CRT). DFS analysis revealed that patients who underwent 3D-CRT after resection had the longest DFS. Patients who underwent IMRT after resection had longer OS than those who underwent 3D-CRT and longer DFS than those who underwent SBRT.

CONCLUSION

HCC patients who undergo liver cancer resection must consider distinct advantages and disadvantages when choosing between SBRT and 3D-CRT. IMRT, a RT technique that is associated with longer OS than 3D-CRT and longer DFS than SBRT, may be a preferred option.

Long-term outcome of centrally located hepatocellular carcinoma treated by neoadjuvant radiotherapy and radical resection: a propensity score matched study

Objective

Centrally located hepatocellular carcinoma (HCC) typically presents challenges in surgical intervention and is associated with a bleak prognosis. In order to address this pressing issue, it is imperative to identify a comprehensive treatment approach, such as neoadjuvant radiotherapy (neoRT), that can enhance the prognosis of patients diagnosed with centrally located HCC.

Methods

Patients who had surgical resections for HCC between March 2015 and December 2020 were included in the study. Patients were assigned to either the neoRT combined with liver resection (neoRT+LR) group or the liver resection alone (LR) group. The study employed propensity-score analysis and Cox proportional-hazards regression models as research methodologies. Using the Kaplan-Meier method, overall survival (OS) and disease-free survival (DFS) were estimated in patients.

Results

During the study, 162 patients were enrolled, with 41 receiving neoRT+LR and 121 receiving LR. The duration of the median follow-up period was 45 months. The 1-year, 3-year, and 5-year OS rates were 95, 70, and 70% for patients in the neoRT+LR group, and 82, 64, and 54% for patients in the LR group, respectively. The 1-year, 3-year, 5-year DFS rates were 71, 53, and 37% for patients in the neoRT+LR group, and 52, 38, and 34% for patients in the LR group, respectively. A successful matching of 37 patients was achieved through propensity-score analysis. OS and DFS after matching analysis was statistically different between the two groups ( P=0.0099, P=0.034, respectively). neoRT was an independent prognostic factor for OS and DFS [hazard ratio (HR)=0.47, 95% CI: 0.24-0.93; HR=0.56, 95% CI: 0.34-0.92, respectively]. According to matching analysis, there were no statistically significant differences observed in terms of baseline characteristics, surgical safety, and complications between the groups.

Conclusion

Liver resection and neoRT can be advantageous for patients with centrally located HCC.

Ablative and non-surgical therapies for early and very early hepatocellular carcinoma: a systematic review and network meta-analysis

Background

A wide range of ablative and non-surgical therapies are available for treating small hepatocellular carcinoma in patients with very early or early-stage disease and preserved liver function.

Objective

To review and compare the effectiveness of all current ablative and non-surgical therapies for patients with small hepatocellular carcinoma (≤ 3 cm).

Design

Systematic review and network meta-analysis.

Data sources

Nine databases (March 2021), two trial registries (April 2021) and reference lists of relevant systematic reviews.

Review methods

Eligible studies were randomised controlled trials of ablative and non-surgical therapies, versus any comparator, for small hepatocellular carcinoma. Randomised controlled trials were quality assessed using the Cochrane Risk of Bias 2 tool and mapped. The comparative effectiveness of therapies was assessed using network meta-analysis. A threshold analysis was used to identify which comparisons were sensitive to potential changes in the evidence. Where comparisons based on randomised controlled trial evidence were not robust or no randomised controlled trials were identified, a targeted systematic review of non-randomised, prospective comparative studies provided additional data for repeat network meta-analysis and threshold analysis. The feasibility of undertaking economic modelling was explored. A workshop with patients and clinicians was held to discuss the findings and identify key priorities for future research.

Results

Thirty-seven randomised controlled trials (with over 3700 relevant patients) were included in the review. The majority were conducted in China or Japan and most had a high risk of bias or some risk of bias concerns. The results of the network meta-analysis were uncertain for most comparisons. There was evidence that percutaneous ethanol injection is inferior to radiofrequency ablation for overall survival (hazard ratio 1.45, 95% credible interval 1.16 to 1.82), progression-free survival (hazard ratio 1.36, 95% credible interval 1.11 to 1.67), overall recurrence (relative risk 1.19, 95% credible interval 1.02 to 1.39) and local recurrence (relative risk 1.80, 95% credible interval 1.19 to 2.71). Percutaneous acid injection was also inferior to radiofrequency ablation for progression-free survival (hazard ratio 1.63, 95% credible interval 1.05 to 2.51). Threshold analysis showed that further evidence could plausibly change the result for some comparisons. Fourteen eligible non-randomised studies were identified (n ≥ 2316); twelve had a high risk of bias so were not included in updated network meta-analyses. Additional non-randomised data, made available by a clinical advisor, were also included (n = 303). There remained a high level of uncertainty in treatment rankings after the network meta-analyses were updated. However, the updated analyses suggested that microwave ablation and resection are superior to percutaneous ethanol injection and percutaneous acid injection for some outcomes. Further research on stereotactic ablative radiotherapy was recommended at the workshop, although it is only appropriate for certain patient subgroups, limiting opportunities for adequately powered trials.

Limitations

Many studies were small and of poor quality. No comparative studies were found for some therapies.

Conclusions

The existing evidence base has limitations; the uptake of specific ablative therapies in the United Kingdom appears to be based more on technological advancements and ease of use than strong evidence of clinical effectiveness. However, there is evidence that percutaneous ethanol injection and percutaneous acid injection are inferior to radiofrequency ablation, microwave ablation and resection.

Study registration

PROSPERO CRD42020221357.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment (HTA) programme (NIHR award ref: NIHR131224) and is published in full in Health Technology Assessment; Vol. 27, No. 29. See the NIHR Funding and Awards website for further award information.

Consensus on the tertiary prevention of primary liver cancer

To effectively prevent recurrence, improve the prognosis and increase the survival rate of primary liver cancer (PLC) patients with radical cure, the Chinese Society of Hepatology, Chinese Medical Association, invited clinical experts and methodologists to develop the Consensus on the Tertiary Prevention of Primary Liver Cancer, which was based on the clinical and scientific advances on the risk factors, histopathology, imaging finding, clinical manifestation, and prevention of recurrence of PLC. The purpose is to provide a current basis for the prevention, surveillance, early detection and diagnosis, and the effective measures of PLC recurrence.

Adjuvant Lenvatinib Plus PD-1 Antibody for Hepatocellular Carcinoma with High Recurrence Risks After Hepatectomy: A Retrospective Landmark Analysis

Purpose

To evaluate the efficacy and safety of lenvatinib plus programmed death-1 (PD-1) antibody as postoperative adjuvant therapy in patients with hepatocellular carcinoma (HCC) at high risks of recurrence.

Patients and Methods

A series of 137 patients with HCC at high risks of recurrence who underwent hepatectomy at our hospital between October 2019 and January 2022 were retrospectively analyzed. Recurrence-free survival (RFS), overall survival (OS), and treatment-related adverse events (TRAEs) were assessed. Landmark analysis was used to compare short- and long-term RFS. Univariable and multivariable analyses were used to identify prognostic factors, and subgroup analyses were performed according to high risks of recurrence.

Results

A total of 85 patients underwent hepatectomy alone and 52 patients received postoperative adjuvant therapy. Compared with the hepatectomy group (HG), RFS was significantly improved in the adjuvant therapy group (ATG) (P < 0.001), but OS was not (P = 0.098). Landmark analysis revealed that RFS within 6 months of the HG was significantly different from that of the ATG (P < 0.001) but not after 6 months (P = 0.486). Multivariable analysis showed that without adjuvant therapy, high Child-Pugh classification, high alpha-fetoprotein levels, microvascular invasion, and satellite lesions were independent risk factors for recurrence within 6 months after hepatectomy. Subgroup analysis revealed that patients with MVI significantly benefited from adjuvant therapy in RFS. But for OS, adjuvant therapy was only significantly effective in patients with single tumor. The most common treatment-related adverse events during adjuvant therapy were hypertension (36.5%), rash or itching (28.8%), diarrhea (23.1%), and fatigue (21.2%).

Conclusion

Postoperative adjuvant lenvatinib plus PD-1 antibody significantly improved RFS in patients with HCC at high risks of recurrence with acceptable safeties.

Comparison of different adjuvant therapy regimen efficacies in patients with high risk of recurrence after radical resection of hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) has a high recurrence rate even after radical surgery. Postoperative adjuvant transhepatic arterial chemoembolization (PA-TACE), postoperative adjuvant hepatic arterial infusion chemotherapy (PA-HAIC), postoperative adjuvant radiotherapy (PA-RT), and postoperative adjuvant molecular targeted therapy have been demonstrated to be effective in reducing the postoperative recurrence rate. The present network meta-analysis was conducted to compare the effects of PA-TACE, PA-HAIC, PA-RT and postoperative adjuvant molecular targeted therapy on the overall survival (OS) and disease-free survival (DFS) in HCC patients after radical resection and to determine the optimal treatment strategy.

METHODS

Network meta-analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed, Embase, Cochrane Library, and Web of Science were used to collect eligible studies up to December 25, 2022. Studies related to PA-TACE, PA-HAIC, and postoperative adjuvant molecular targeted therapy after radical HCC resection was included. The endpoints were OS and DFS, and the effect size was determined using hazard ratio with a 95% confidence interval. R software and "gemtc" package were employed to analyze the results.

RESULTS

A total of 38 studies involving 7079 patients with HCC after radical resection were ultimately enrolled to be analyzed. Four postoperative adjuvant therapy measures and two oncology indicators were evaluated. In this study, OS-related investigations validated that PA-Sorafenib and PA-RT markedly enhanced the OS rates in patients after radical resection when compared to PA-TACE and PA-HAIC. However, statistical analysis revealed no significant difference between PA-Sorafenib and PA-RT, as well as PA-TACE and PA-HAIC. In the DFS-related investigations, PA-RT demonstrated superior efficacy over PA-Sorafenib, PA-TACE, and PA-HAIC. Additionally, PA-Sorafenib displayed better efficacy than PA-TACE. Nevertheless, there was no statistical significance between PA-Sorafenib and PA-HAIC, as well as PA-TACE and PA-HAIC. We also performed a subgroup analysis of studies focusing on HCC complicated by microvascular invasion after radical resection. In terms of OS, both PA-RT and PA-Sorafenib demonstrated a noteworthy improvement over PA-TACE, whereas no statistical significance was detected between PA-RT and PA-Sorafenib. Likewise, for DFS, both PA-Sorafenib and PA-RT exhibited superior efficacy compared to PA-TACE.

CONCLUSION

In patients with HCC after radical resection and a high risk of recurrence, both PA-Sorafenib and PA-RT significantly improved OS and DFS when compared to PA-TACE and PA-HAIC. Notably, PA-RT exhibited superior efficacy over PA-Sorafenib, PA-TACE, and PA-HAIC in terms of DFS. Similarly, PA-Sorafenib appeared to be more effective than PA-TACE for DFS.

Clinical Benefits of Neoadjuvant Radiotherapy on the Postoperative Recurrence of Centrally Located Hepatocellular Carcinoma: A Real-World Evidence Based on Phase II Clinical Trial

Objective

Although surgical resection is one of the most effective way to treat liver cancer, its efficacy and safety in treatment of centrally located hepatocellular carcinoma (HCC) remains elusive. Therefore, it is very important to find a comprehensive treatment mode, such as radical resection combined with neoadjuvant radiotherapy (neoRT).

Methods

The centrally located HCC patients who underwent radical resection from July 2015 to April 2021 were enrolled. According to whether the neoRT was implemented or not, these patients were allocated into neoadjuvant radiotherapy combined with liver resection (neoRT+LR) and liver resection alone (LR) group. The research method used propensity-score analysis and Cox proportional-hazards regression models. We generated an E-value to assess the sensitivity to unmeasured confounding. This study is a real-world, retrospective study based on phase II clinical trial.

Results

A total of 168 patients were enrolled, including 38 patients treating with neoRT+LR and 130 patients with LR. The 1-, 3-, 5-year disease free survival (DFS) rates were 74%, 55% and 39% in the neoRT+LR group, and 44%, 28%, and 24% in the LR group, respectively. Neoadjuvant radiotherapy was an independent prognostic factor for postoperative recurrence ([HR]0.42, 95% CI [0.25, 0.69]). There was significant association between neoRT+LR and longer disease-free survival (Match, [HR] 0.43, 95% CI [0.24, 0.76]; GenMatch, [HR] 0.32, 95% CI [0.23, 0.43]; Adjusted for propensity score, [HR] 0.41, 95% CI [0.23, 0.73]; Inverse probability weighting, [HR] 0.38, 95% CI [0.22, 0.65], respectively). DFS before and after matching analysis was statistically different in two groups (p-value=0.005, p-value=0.0024, respectively). Neoadjuvant radiotherapy can significantly reduce the postoperative early recurrence (p-value <0.05). E-value analysis suggested robustness to unmeasured confounding.

Conclusion

Liver resection combined with neoadjuvant radiotherapy was effective and safe for treatment of centrally located HCC patients, which improved the prognosis of patients and reduced the incidence of early recurrence.

Analysis of conditional survival in primary hepatocellular carcinoma after narrow-margin hepatectomy: a large-sample, dual-centre, retrospective study

BACKGROUND

Overall survival (OS) reflects the constant hazard and survival probabilities calculated from the initial follow-up. Conditional survival (CS) dynamically estimates prognosis based on survival time after treatment. This study aimed to estimate CS in patients who had undergone narrow-margin hepatectomy for primary hepatocellular carcinoma.

METHODS

The clinical data of 1010 eligible patients between 2012 and 2017 were retrospectively analysed. The equation CS1=OS(x+1)/OS(x) was used to calculate the probability of an additional 1-year survival in patients who had survived for x years.

RESULTS

Tumour differentiation, microvascular invasion, and tumour emboli were independent risk factors for OS. Actuarial survival decreased from 91.53% at 1 year after hepatectomy to 48.92% at 4 years, whereas CS1 increased from 69.45% at 1 year to 94.62% at 4 years. The difference was more obvious in the tumour-emboli subgroup, with an OS of 26.38% at 5 years versus a CS1 of 88.91% at 4 years following narrow-margin hepatectomy (Δ62.53%).

CONCLUSION

CS is potentially useful in providing a dynamic evaluation of survival, predicting prognosis more accurately than OS during follow-up, and formulating more appropriate treatment measures based on disease progression.

Advances in postoperative adjuvant therapy for primary liver cancer

Hepatocellular carcinoma (HCC) is a highly heterogeneous, invasive, and conventional chemotherapy-insensitive tumor with unique biological characteristics. The main methods for the radical treatment of HCC are surgical resection or liver transplantation. However, recurrence rates are as high as 50% and 70% at 3 and 5 years after liver resection, respectively, and even in Milan-eligible recipients, the recurrence rate is approximately 20% at 5 years after liver transplantation. Therefore, reducing the postoperative recurrence rate is key to improving the overall outcome of liver cancer. This review discusses the risk factors for recurrence in patients with HCC radical surgical resection and adjuvant treatment options that may reduce the risk of recurrence and improve overall survival, including local adjuvant therapy (e.g., transcatheter arterial chemoembolization), adjuvant systemic therapy (e.g., molecular targeted agents and immunotherapy), and other adjuvant therapies (e.g., antiviral and herbal therapy). Finally, potential research directions that may change the paradigm of adjuvant therapy for HCC are analyzed.

Systematic review of adjuvant external beam radiotherapy for hepatocellular carcinoma following radical hepatectomy

BACKGROUND AND AIM

Recurrence remains the main bottleneck hindering outcomes of hepatectomy for hepatocellular carcinoma (HCC). Owing to technological advances, external beam radiotherapy (EBRT) is being increasingly used in the management of HCC; however, there is no consensus on the role of adjuvant EBRT following hepatectomy.

METHODS

A systematic review was conducted according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. PubMed, MedLine, Embase, the Cochrane Library, Web of Knowledge were used to screen eligible studies (published as of May 1st, 2022) that evaluated the clinical safety and efficacy of EBRT for HCC receiving hepatectomy. The endpoints were disease-free survival (DFS), overall survival (OS), and adverse events (AEs).

RESULTS

A total of ten studies were eligible (three randomized controlled trials, one phase II trial, and six retrospective comparative studies). The pooled hazard ratio (HR) for median DFS and OS were both in favor of adjuvant EBRT compared with surgery alone (all P<0.05), and the advantage of adjuvant EBRT was also confirmed in subgroups stratified by different populations (narrow margin, P<0.05; microvascular invasion, P<0.05; portal vein tumor thrombus, P<0.05) and study designs (prospective studies, P<0.05; retrospective studies, P<0.05). Adjuvant EBRT was also found to be superior to adjuvant TACE (P<0.05). Pooled rates of overall AEs and severe AEs were 65.3% and 12.2%, but no fatal AEs were reported.

CONCLUSION

Adjuvant EBRT can be considered for HCC patients, especially those with a high risk of recurrence. Further studies are required for validation of these findings.

A Prospective Study of Liver Regeneration After Radiotherapy Based on a New (Su'S) Target Area Delineation

Background

In this study, we designed a new (Su’S) target area delineation to protect the normal liver during liver regeneration and prospectively evaluate liver regeneration after radiotherapy, as well as to explore the clinical factors of liver regeneration and established a model and nomogram.

Methods

Thirty patients treated with preoperative downstaging radiotherapy were prospectively included in the training cohort, and 21 patients treated with postoperative adjuvant radiotherapy were included in the validation cohort. The cut-off points of each optimal predictor were obtained using receiver-operating characteristic analysis. A model and nomogram for liver regeneration after radiotherapy were developed and validated.

Results

After radiotherapy, 12 (40%) and 13 (61.9%) patients in the training and validation cohorts experienced liver regeneration, respectively. The risk stratification model based on the cutoffs of standard residual liver volume spared from at least 20 Gy (SVs20 = 303.4 mL/m²) and alanine aminotransferase (ALT=43 u/L) was able to effectively discriminate the probability of liver regeneration. The model and nomogram of liver regeneration based on SVs20 and ALT showed good prediction performance (AUC=0.759) in the training cohort and performed well (AUC=0.808) in the validation cohort.

Conclusions

SVs20 and ALT were optimal predictors of liver regeneration. This model may be beneficial to the constraints of the normal liver outside the radiotherapy-targeted areas.

Inhibiting p21-activated kinase (PAK7) enhances radiosensitivity in hepatocellular carcinoma

OBJECTIVE

In light of the upregulation of p21-activated kinase (PAK7) in a variety of cancers, including hepatocellular carcinoma (HCC), we aimed to investigate the effect of PAK7 on the sensitivity of HCC cells to radiotherapy.

METHODS

PAK7 expression was determined in normal adult liver epithelial THLE-2 and human HCC cell lines. The effect of ionizing radiation (IR) on the HCC cell viability was evaluated by Sulforhodamine B (SRB) assay. HCC cell lines Mahlavu and Huh7 were chosen to assess the effect of PAK7 shRNAs on the viability, clone formation, apoptosis, cycle distribution and γ-H2AX expression after exposure to IR.

RESULTS

As compared to THLE-2 cells, PAK7 was upregulated in poorly differentiated Mahlavu and SK-Hep-1 cells, but moderately or lowly expressed in well-differentiated Huh7 and HepG2 cells. HCC cells with moderate or low expression of PAK7 presented a decreased viability at 2 Gy IR, which had no significant effect on PAK7_high HCC cells. Mahlavu and Huh7 cells transfected with PAK7 shRNAs showed increased inhibitory effect of IR on viability. In addition, PAK7 shRNAs reduced clone formation, facilitated the cell apoptosis, arrested cells at G2/M phase, and increased γ-H2AX expression. Moreover, changes above were more evident in the HCC cells co-treated with IR and PAK7 shRNAs.

CONCLUSION

PAK7 downregulation could inhibit the viability, promote the apoptosis, arrest cells in G2/M phase, and induce the DNA damage in HCC cells, thereby enhancing the radiosensitivity in HCC.