The review, led by Ying Liu, Linke Bian, and colleagues at Shanghai East Hospital, Tongji University, systematically maps how locoregional ablation reshapes the tumor immune microenvironment and why pairing it with immunotherapy is biologically compelling. The authors are careful, however, to draw a hard line between mechanism and proof: most of the supporting evidence remains preclinical or comes from small, non-randomized studies, and no robust phase III data yet demonstrate a survival benefit for ablation-immunotherapy combinations in liver cancer.

The core concept is immunogenic cell death. Ablation creates a characteristic three-layer injury zone: a central necrotic core, a transitional zone of sublethal stress, and surrounding viable tissue. Dying cells release tumor-associated antigens and damage-associated molecular patterns in a temporally ordered sequence—surface calreticulin acting as an early “eat-me” signal for dendritic cells, secreted ATP recruiting and activating innate immunity through NLRP3 inflammasome signaling, and finally passive release of HMGB1 and heat shock proteins that drive dendritic cell maturation. Together these signals can prime CD8-positive T cells capable of attacking tumor cells far beyond the treated site, the so-called abscopal effect.

But the immune response ablation provokes is self-limiting. Within days, residual tumor cells upregulate PD-L1, exhausted T cells accumulate inhibitory receptors such as Tim-3 and CD244, and regulatory T cells and myeloid-derived suppressor cells flood the ablation margin. Natural killer cell dynamics tell a similar story: while ablation can boost NK-mediated interferon-gamma production, an expansion of immature CD56-positive CD16-negative NK cells one month after radiofrequency ablation predicts recurrence. The result is a window of immune activation that closes before durable memory is established.

The review’s most striking mechanistic finding concerns incomplete ablation, or iRFA—residual tumor surviving in the sublethal transitional zone, a particular risk for tumors of three centimeters or larger or those near major vessels where blood flow dissipates heat. Surviving cells undergo epithelial-mesenchymal transition and angiogenic reprogramming, and, critically, sublethal thermal stress triggers SUMO2-mediated SUMOylation that suppresses type I interferon signaling, impairing dendritic cell maturation and T cell infiltration. Incomplete ablation thus couples residual tumor substrate with active immunosuppression, converting a zone of potential immune priming into one of tolerance. The authors argue that preventing iRFA through better planning and image guidance is a prerequisite for any combination strategy to work.

Not all modalities are immunologically equivalent. Thermal techniques such as radiofrequency and microwave ablation release broad antigen loads but risk heat-induced antigen denaturation. Cryoablation preserves antigens in near-native conformation, favoring uptake by antigen-presenting cells, while irreversible electroporation engages multiple regulated cell death pathways—pyroptosis and necroptosis among them—while preserving vascular and extracellular scaffolds that ease immune cell infiltration. The trade-offs include procedural complexity and, rarely, cryoshock after extensive hepatic treatment.

On the clinical side, the evidence is promising but thin. Adding radiofrequency or microwave ablation to ongoing nivolumab raised the objective response rate from 10 to 24 percent in a prospective cohort of 50 patients. Tremelimumab combined with subtotal ablation produced a median time to progression of 7.4 months with increased intratumoral CD8-positive infiltration in a 32-patient pilot. A phase I/II trial of OK-432-stimulated dendritic cells injected after radiofrequency ablation extended recurrence-free survival from 13.0 to 24.8 months, though overall survival was unchanged. Irreversible electroporation paired with allogeneic NK cell infusion showed feasibility signals in small studies. None of these results, the authors stress, substitutes for randomized validation.

The combination toolbox extends well beyond checkpoint inhibitors. Pattern recognition receptor agonists—CpG oligonucleotides, STING agonists, GM-CSF—can enforce dendritic cell licensing at the ablation site. Oncolytic viruses such as G47Δ, given before ablation so infected cells can replicate, amplified T cell responses in mouse models, though the negative phase III PHOCUS trial of Pexa-Vec in HCC is a sobering reminder that preclinical immune activation does not guarantee clinical survival benefit. Nanobiomaterial platforms add a third layer: hydrogels and nanoparticles that co-localize ablation-released antigens with adjuvants, sustain release over days, or ferry captured tumor debris to draining lymph nodes for concentrated T cell priming.

Timing emerges as a central unresolved question. Immune profiling after irreversible electroporation suggests a systemic innate activation window roughly three to fourteen days after treatment—a plausible interval for starting checkpoint inhibitors or adoptive cell therapy, but one derived from limited kinetic observations rather than prospective schedule comparisons. The review also distinguishes three therapeutic settings with different goals: adjuvant therapy after curative ablation, where the endpoint is recurrence-free survival; cytoreductive ablation during systemic immunotherapy for advanced disease, where progression-free survival and response rates matter; and salvage of incomplete ablation, where complete local eradication must remain the priority and immunotherapy is an investigational adjunct.

The authors’ verdict is measured. Mechanistic understanding has substantially outpaced clinical validation, and reliable predictive biomarkers—tumor immunophenotype, circulating NK cell function, post-ablation ctDNA dynamics, neutrophil-to-lymphocyte ratio—remain unvalidated in this setting. Response assessment needs immune-adapted criteria such as iRECIST to capture pseudoprogression and abscopal regression. Still, the conceptual framework is coherent: ablation as an in situ vaccine, immunotherapy as the amplifier that converts a transient spark into durable systemic memory. Prospective, biomarker-stratified trials with serial immune profiling will determine whether that logic translates into longer lives for liver cancer patients.

Subject of Research: Combining locoregional tumor ablation with immunotherapy to enhance antitumor immunity in hepatocellular carcinoma

Article Title: Synergistic strategies of tumor ablation and immunotherapy in hepatocellular carcinoma: mechanisms, clinical translation, and perspectives

Article References: Liu, Y., Bian, L., Wang, H., Cui, D., Wu, Z., & Zhai, B. (2026). Synergistic strategies of tumor ablation and immunotherapy in hepatocellular carcinoma: mechanisms, clinical translation, and perspectives. Holistic Integrative Oncology, 5(1), Article 82. https://doi.org/10.1007/s44178-026-00303-7

Image Credits: AI Generated

DOI: 10.1007/s44178-026-00303-7

Keywords: hepatocellular carcinoma, tumor ablation, immunotherapy, immunogenic cell death, tumor microenvironment, radiofrequency ablation, cryoablation, irreversible electroporation, immune checkpoint inhibitors, abscopal effect, incomplete ablation, nanobiomaterials