Hepatocellular Carcinoma Intrinsic Cell Death Regulates Immune Response and Prognosis

New insights into mechanisms and interventions of locoregional therapies for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is responsible for a significant number of cancer-related deaths worldwide and its incidence is increasing. Locoregional treatments, which are precision procedures guided by imaging to specifically target liver tumors, play a critical role in the management of a substantial portion of HCC cases. These therapies have become an essential element of the HCC treatment landscape, with transarterial chemoembolization (TACE) being the treatment of choice for patients with intermediate to advanced stages of the disease. Other locoregional therapies, like radiofrequency ablation, are highly effective for small, early-stage HCC. Nevertheless, the advent of targeted immunotherapy has challenged these established treatments. Tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs) have shown remarkable efficacy in clinical settings. However, their specific uses and the development of resistance in subsequent treatments have led clinicians to reevaluate the future direction of HCC therapy. This review concentrates on the distinct features of both systemic and novel locoregional therapies. We investigate their effects on the tumor microenvironment at the molecular level and discuss how targeted immunotherapy can be effectively integrated with locoregional therapies. We also examine research findings from retrospective studies and randomized controlled trials on various combined treatment regimens, assessing their validity to determine the future evolution of locoregional therapies within the framework of personalized, comprehensive treatment.

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.

Efficacy of Αtezolizumab-Βevacizumab in BCLC-C cirrhotic patients with hepatocellular carcinoma according to the type of disease progression, the type of BCLC-C and liver disease severity

PURPOSE

The aim of our study was to evaluate, under real-life conditions, survival of patients with advanced HCC (BCLC-C), either initially presenting in that stage or migrating from BCLC-A to BCLC-C within 2 years after curative LR/RFA, treated either with Atezolizumab-Bevacizumab or TKIs.

METHODS

Sixty-four cirrhotic patients with advanced HCC, who either initially presented as BCLC-C and were treated with Atezo-Bev (group A, N = 23) or TKIs (group B, N = 15) or who migrated from BCLC-A to BCLC-C stage within 2 years after LR/RFA and were either treated with Atezo-Bev (group C, N = 12) or TKIs (group D, N = 14), were retrospectively evaluated.

RESULTS

The four groups were comparable for all baseline parameters (demographics/platelets/liver disease etiology/diabetes/varices/Child-Pugh stage/ALBI grade) except for CPT score and MELD-Na. Using Cox-regression analysis, we observed that survival of group C after systemic treatment onset was significantly higher compared to group A (HR 3.71, 1.20-11.46, p = 0.02) and presented a trend to statistical significance when compared to group D (HR 3.14, 0.95-10.35, p = 0.06), adjusted for liver disease severity scores. When all BCLC-C patients classified as such due to PS only were excluded from the study, a trend for the same survival benefit in group C was shown, even in the most difficult-to-treat population with extrahepatic disease or macrovascular invasion.

CONCLUSION

Cirrhotic patients with advanced HCC initially diagnosed in BCLC-C, exhibit the worst survival irrespective of treatment schedule, whereas patients progressing to BCLC-C following disease recurrence after LR/RFA, seem to mostly benefit from Atezo-Bev, even patients with extrahepatic disease and/or macrovascular invasion. Liver disease severity seems to drive survival of these patients.